Small Taxonomy Pools

When it comes to taxonomy, few of us outside of the related fields know how many species it covers (taxonomists estimate there have been hundreds of millions of species of life forms on this planet up to now, an estimated 8.7 million of which are alive today). The number of species we are familiar with makes up less than 1% of even the known species.

Thus fiction will end up showing a few stock species, due to that familiarity. Some groups of plants and animals can have thousands of known species, and fiction will only mention about two. Often this results in Misplaced Wildlife, as the particular species shown wouldn't live in a certain place, but we wouldn't know of the other species that do (unless the writers are showing their work).

There is also a bit of a sliding scale. On the low end, entire phyla (aka divisions in botany) can have just one or two species represented. On the high end, a single family can have more than half a dozen species commonly shown. This is regardless of the actual number of species per group.

Filming on location can produce a fair sampling of the local flora, including the species no one much has heard of, but the plants named will still come from a small pool.

Often this trope is because a particular species is featured in a work that puts that species in the popular consciousness, but there are other causes. Many kinds of creatures are rarely seen in fiction because they are just as rarely seen in real life. (When was the last time you met a caecilian, mantis shrimp, or a tuatara?)

A Sub-Trope of Small Reference Pools. Contrast Improbable Taxonomy Skills, the ability to fully classify an organism with just a cursory examination.

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Examples, split along taxonomic groupings:

Single Cell Organisms Without Nuclei or Membrane-Bound Organelles (domains Bacteria and Archaea; formerly considered a single domain Prokaryota)

• Bacteria are more often known by the diseases they cause than the actual organisms. Some are often confused with viruses. There are more beneficial, non-pathogenic bacteria than pathogenic bacteria, outside and even inside the human body, but this fact is often overlooked.
  • E. coli (properly known as Escherichia coli) is particularly prone to this: Everyone talks about it like it's a dangerous pathogen, when actually only one strain (O157:H7) is what they're referring to. In reality the vast majority of strains are non-pathogenic and the vast majority of pathogenic strains relatively innocuous. The relatively innocuous kind is living inside you right now.
• Impressively averted in Moyashimon, which name-checks a number of bacteria and viruses, as well as a number of yeasts and other one-celled organisms.
• Archaea do not exist in fiction. The fact that you need some knowledge of biochemistry to even understand what they are^note prokaryotes with DNA wrapped around histones, a membrane using ether-bonded terpenes instead of ester-bonded fatty acids, and eukaryote-like RNA polymerase, among other things may have something to do with it, as does the fact that they weren't proposed as a separate kingdom until 1977 and weren't officially called Archaea until the '90s. Even then they were believed to be found only in hot springs and hydrothermal vents until being found to make up a large portion of the world's poorly-studied plankton in the late '90s.
• Even when prokaryotes are correctly named in visual media, they're usually played by some kind of protist, as these tend to be more photogenic. Wriggling cilia simply look better on-screen than anonymous dots and bacilli.

Organisms With Nuclei or Membrane-Bound Organelles (domain Eukaryota; plants, animals, fungi listed in separate sections)

• Algae probably don't even have a specific species mentioned, just the group as a whole. The vanishingly-rare exception, when an alga species might be referred to by its common name, is if someone is cooking it.
• Most protists featured tend to be either some species of Paramecium or Amoeba. Their vast diversity is usually ignored.
• Good luck finding any creature being called a protist.
• Algae is not actually a plant.
  • The fact that algae is photosynthetic and looks like a plant doesn't help. The same tends to go for other algae, depending on how much there is in one spot. The distinction gets blurred even further when you find out that plants evolved from algae...
  • Seaweed are a polyphyletic group. Some are plants, some are chromalveolates (such as kelp), and some fall under a phylum without a kingdom, such as the rhodophytes (red algae).
• Any time microorganisms (of any sort) are shown in visual media, they're guaranteed to be one of the more photogenic members of this group, usually Paramecium, Stentor, or Vorticella. That's assuming it's not a rotifer (animal) that they're passing off as a protist.
• In general, unless they are anthropomorphic characters, expect most plants, algae and fungi to be treated as objects or scenery. They may get a MacGuffin or Companion Cube treatment if they are non-anthropomorphic.

Fungi (often thought to be plants, but a different group actually more closely related to animals)

• Mold — Although anyone who's seen food go rotten knows there are several kinds of mold (depending on the color of the rot), no species is known by name. Even Penicillium chrysogenum is just known by the antibiotic based from it, penicillin. Slime molds and water molds are polyphyletic and consist of several supergroups, none of which fit in the fungi kingdom.
• Yeast — Also, no species is known by name. It's just commonly known as one of two things: A fermentation agent, although there are still several different kinds of species for that, and as whatever species causes yeast infection, which are the species of the genus Candida.
• Truffle — Again, just the group known, not any species. And they are only mentioned when someone is making some kind of fancy meal, or getting ingredients for one. Cooking shows will differentiate between black and white truffles. The fact that there is more than one type of black truffle (black Périgord truffle being the good one), or even just more than two types of truffles never gets mentioned. White truffles are rarer than the Périgords and tend to carry a sort of elitist appeal to them... even more than the elitism that plain old Périgords have. Most people can't tell the difference and restaurants have been known to dose the milder white truffles with Périgord oil so the diners taste the distinctive truffle flavor. Scams abound with lesser quality black truffles also being dosed in the same manner and sold for obscene prices.
• Edible mushrooms might be mentioned by name, such as morels or shiitake. Poisonous ones are invariably called "toadstools" or just "poisonous mushroom" even though there are an awful lot of mycotoxin-containing species. If one is mentioned, it will probably be the destroying angel simply because it has the most badass name ever. Not coincidentally it's one of the most toxic and most easily misidentified mushrooms in the wild. In The Dresden Files book "Grave Peril" Jim Butcher gets it exactly right with his description of how eating a destroying angel will kill you. He even gets the antidote spot-on, which is kind of justified. Some are ridiculously hard to identify without specialized equipment and even mycologists are known to argue about which are which. This is also very culturally dependent. East European and Asian cuisine uses a lot more mushrooms than Western or American, so people from the former areas are likely to be able to identify a much longer list of edible species and (if they're the type to go mushroom hunting themselves) to be able to recognize poisonous ones. However this can backfire horribly if they move if they move to Western countries as several very poisonous varieties native to Western countries strongly resemble edible fungi from their original locales.
• Shelf fungi occasionally rate a mention as scenery.

Plants

• In general plants that are not angiosperms (flowering plants) or conifers pretty much do not exist in media. This is somewhat understandable since the former especially dominate most ecosystems nowadays, but there is still quite a variety of environments dominated by things like moss, ferns and horsetails and they were twice as abundant in prehistoric times... in which things set in them still rarely feature them (even documentaries).
• Pteridophyta (ferns) are never referred to by species... ever. There are some 12,000 current species and countless others that didn't survive much past the Cretaceous. You can bet that if a work references ferns at all, they will either have mystical properties, or the story in question will take place during the Cretaceous period or earlier (these two options are not mutually exclusive). Bonus (negative) points if anyone makes reference to flowers or seeds of a fern. Bonus (positive) points if someone makes reference to fern spores, or mentions a specific species.
• The conifers are an entire phylum of plant species, yet all fiction seems to mention are "pines" and "firs" (both of which are genera themselves). "Redwoods" (a casual name, not a formal taxonomic designation) and "blue spruce" (a single species) run a distant third and fourth, and there's very rarely a distinction made between coastal redwood and giant sequoia.
  • Holiday specials sometimes refer to "Christmas trees" as if they're a distinct species of tree, not a purpose for which a number of small, densely-branched conifers (mostly pines or firs) are cultivated.
  • The existence of junipers is sometimes acknowledged, if only because their odor helps set the ambiance for desert scenes.
  • Translations of Scandinavian works invariably refer to conifers as "spruce" — the botanical equivalent of the original gran. This makes the trees more highly "marked" (in the linguistic sense) than if they had been casually rendered as "pine".
• Cycads are seldom seen outside shows and documentaries set in the Mesozoic.
• Temperate angiosperm trees are fairly well represented, if only because there aren't that many to choose from. Tropical trees, less so.
• Flowers are mostly those with well known associations — roses for romance, carnations for buttonholes, poppies for remembrance. Characters will very seldom talk about their geraniums and fuchsias. Except for little old ladies who dabble at gardening: geraniums are the flower of choice then. Rhododendrons are occasionally mentioned, if only to put a name to the ornamental bush which a voyeur or eavesdropper hides behind.
• There are three types of grass: lawn, cereal, and bamboo. Adventurers in a swamp may encounter sawgrass.
• With 22,000-25,000 species in the family Orchidaceae, the one on-screen is invariably one of the most common decorative Phalaenopsis. Extra fail points if it's also Misplaced Vegetation and/or being described as an "exotic new species". Extra bonus fail points if it's called a "species" at all since almost any Phal. you will find in cultivation will be a complex hybrid.
• Carnivorous plants are rarely represented as anything but pure fantasy with giant man-eating snapping jaws and writhing vines. If they are a real species, they'll almost always be Venus flytraps. There are probably close to 1000 different species of insectivorous plants around the world with New World and Asian pitcher plants, sundew, bladderworts, butterworts and others, many of which are perfectly "weird" and photogenic without any fabrication at all. The Venus flytrap gets extra props for Charles Darwin calling it "the most wonderful plant in the world".
• Eucalypts are rarely ever distinguished beyond generic 'gum trees' despite covering a truly staggering number of different species. Even in their native Australia, you might get the occasional references to blue gums or the stark white ghost gums but that's about it.
• The only cactus to regularly be named in fiction are saguaro and prickly pear. The latter is actually a genus containing ~200 species, but saying which kind of prickly pear would spoil the Alliterative Name, so never mind.
• Plants that produce edible things are far more well known by what they produce than the plants themselves. For example, an apple tree and an orange tree will be depicted as exactly the same aside from what fruit is growing on them. Even then, expect to find made-up ones alongside more familiar fruit.
• Palm trees are almost always just scenery, in which role any photogenic species will do. If it has to be something specific, it's usually because the characters are relying on it for food, in which case it's most often a coconut, maybe date or sago palm. (The name "sago palm" also refers to certain cycads.)

Animals

• The animal kingdom actually includes dozens of phyla, with only one of them covering animals with backbones (or pseudo backbones). We'll try to group them appropriately.
• Much like plants, algae and fungi above, if an animal is sessile (fixed to one place) or moves very slowly, expect it to be treated as an object, scenery, MacGuffins or Companion Cube rather than as an actual character unless they are anthropomorphic.

Sponges

• No one species is commonly shown. It's probably because of Spongebob Squarepants that many are even aware sponges are living creatures. We hope. Expect to never see a freshwater sponge. Ever.

Cnidarians

• You're unlikely to get a view of the diversity of the jellyfish (or jellies, if you prefer, class Scyphozoa). When they show up, it's likely they'll be either the common, impressive-looking, and easy-to-handle sea nettles or else something entirely fantastical and possibly electric. You're also likely to hear of the infamously deadly Chironex fleckeri, and it will probably be referred to as the "sea wasp" or "box jellyfish", despite box jellyfish having their own class, Cubozoa.
• Imagine you had 5000 conjoined twins, but some have only legs, others only mouths/stomachs, others only gonads, and some forming grotesque air bladders. Welcome to the world of siphonophores. If you asked the common man what a Portuguese Man o' War was, 99 out of 100 times he'd say "jellyfish". While Men o' War are jellyfish in the sense that they are in the subphylum Medusozoa, that's where the taxonomic similarities end. Men o' War are part of the order Siphonophora in the class Hydrozoa, while the common man's jellyfish is almost always invoking the cup-shaped jellies of the class Schyphozoa. Men o' War are far, far less common in fiction than true jellyfish.
• Corals and sea anemones (class Anthozoa) may be seen, but exactly what type they are isn't often specified. However, if brain coral is shown, it will probably referred to as such.
• You didn't even know hydras (order Anthomedusae) are real animals, did you? They kinda look like pinkish-white gummi worms with numerous regenerating tentacles. They're also a freshwater cnidarian: something that only appears in fiction if the writer is hand-waving the issue of fresh vs. salt water, altogether.

Flatworms and Roundworms

• Pretty much the only members of these phyla seen in fiction are the infamous parasitic worms, notably the tapeworms. They are yet still rare and will only show for Squick or Body Horror purposes (Orifice Evacuation, anyone?).

Annelids

• The most common annelids in fiction are earthworms and leeches (class Clitellata). Polychaete worms don't seem to exist.

Molluscs

• Gastropods: one snail, one slug. Most of the time, they are depicted as either terrestrial or freshwater species, sea slugs like nudibranches, sea butterflies, sea angels, and sea hares are rarely ever shown, with sea snails like whelks, periwinkles, abalones, conches, and limpets being simply just "seashells", and then there's the venomous cone snail...
• Cephalopods (class Cephalopoda):
  • Subclass Coleoidea: Octopuses (order Octopoda) are the most used members of this class, but they are almost always the "generic octopus" with a big mantle and no fins. The absolutely adorable finned octopuses (suborder Cirrina) have no representation other than Pearl from Finding Nemo. Squids (order Teuthida) are represented by the giant squid, with the odd appearance by a generic smaller squid. Cuttlefish (order Sepiida) are common in documentaries, but nonexistent in other works. The vampire squid (order Vampyromorphida) is often used as an example of "creepy deep-sea animal", but is never shown in fiction (other than partially inspiring Malamar from Pokémon and appearing hybridized with an anglerfish in Pi's hallucination in the film adaption of Life of Pi). Ram's Horn squid (order Spirulida) are never shown, though this is not surprising as very little is known about them due to them living extremely deep underwater. Bobtail squid (order Sepiida) are also never shown, even though at least some of them live in shallow water.
  • Subclass Ammonoidea: The ammonite often appears as a generic fossil, but it is almost always has a typical spiral-shelled shape. The cone shaped ammonoids such as Baculites, or the extremely weird looking ones such as Oxybeloceras◊ are never shown.
  • Subclass Nautiloidea: While they look very much like relics of days gone by with their spiral shells, Nautilus and Allonautilus (the only surviving members of this subclass) are almost never shown. The extinct species of nautiloid such as Orthoceras don't get much luck either.
• Bivalvia: Alive, they're only occasionally seen, particularly oysters or giant clams; dead, they're lumped together as seashells unless they're oysters, mussels or scallops, in which case they are "food".

Echinoderms

• Sea urchins (class Echinoidea) are fairly uncommon. You might see some of the flashy black-or-purple spiky-ball variety sea urchin, but no attention will be paid to them.
• Despite there being a large number of sea cucumbers (class Holothuroidea) available to choose from, they remain incredibly unpopular, appearing only to produce the occasional gag (being literal cucumbers on Spongebob Squarepants or spewing sticky white goo on a girl).
• Sea stars (or starfish; class Asteroidea) are one of the most underrepresented animals out there. The only type of sea star that ever appears is the generic five-armed pink-or-tan "Patrick Star" kind. In reality, there are thousands of types of sea stars of various colors, sizes, and arm counts. Some have as many as eleven arms, and can be found in practically any color (though grey and tan are pretty common).
• The crinoids, or sea lilies (class Crinoidea), are totally unheard of, except for Pokémon's Cradily.

Arthropods (Arthropoda):

• Includes sea spiders, horseshoe crabs, insects, arachnids, crustaceans and myriapods. Except for the aquatic species most arthropods in media tend to be erroneously called insects or bugs.

Chelicerates

• Spiders (order Araneae) are usually tarantulas or black widows. The former is most common because they're really large for spiders (which makes them more intimidating to look at), but are also relatively docile for spiders, making them easier to work with (some species do have a painful bite though, and some fling hairs that can cause severe irritation to the skin). Black widows have a nasty bite and a very distinctive appearance. Any spider that isn't one of the two "dangerous" varieties is "generic harmless" and is probably either a garden spider or a harvestman (a.k.a. daddy longlegs), the latter of which isn't really a spider.
• It should be noted that while the harvestman (order Opiliones) is not a spider, the cellar spider which is also called the daddy longlegs is a true spider. Confusion over the name leads to people claiming the cellar spider is not a true spider (especially in regions where they exist but harvestmen do not).
• The only spider webs seen in media are either the beautiful round nets typical of orb weaver species, or else look suspiciously like stretched-out cotton batting. Some spiders do produce webs that look like that, but it's hardly the only other option.
• The emperor scorpion is the only scorpion (order Scorpiones) you'll see in fiction, with very few exceptions. That particular species hits the perfect sweet spot of being huge and impressive looking, mildly poisonous, and very docile.
• You probably won't find horseshoe crabs (class Merostomata), sea spiders (class Pycnogonida), pseudoscorpions (order Pseudoscorpiones), whip scorpions (order Thelyphonida), mites (order Acari), tickspiders (order Ricinulei), sun spiders (order Solifugae), or anything other than spiders, scorpions and maybe ticks featured in fiction. You probably won't even get an acknowledgement that "arachnid" is anything other than a fancy synonym for "eight-legged thing".

Insects

• Whenever there are butterflies (order Lepidoptera) featured in any series, they are almost always the orange and black monarch butterfly. If they aren't monarchs, they're the white cabbage moth, or occasionally a swallowtail. The vibrant blue butterflies in the genus Morpho sometimes feature if the butterflies in question are meant to be either exotic or magical.
• There are beetles (order Coleoptera) for practically every environment and are everywhere. The most recognized beetles out there are dung beetles, rhinoceros beetles, stag beetles, ladybugs/ladybirds and fireflies. If a TV show mentions dermestid beetles, they will almost undoubtedly get it wrong. First, they are never called dermestids — they are generally referred to as "flesh-eating beetles", which is honestly too much of a mouthful for something you work with extremely often in museums or forensic science. Secondly, their species is never identified. There are around 600 species worldwide, but only one is generally useful to museums or forensic scientists: Dermestes maculatus, or the hide beetle. This assumes that you're lucky enough to even see dermestids, and that they haven't subbed them out for the more charismatic Madagascar hissing cockroach.
• Cockroaches (order Blattodea) are common, but we're never told which of the thousands of species is portrayed. If they're just used for a gross-out or scare in a horror movie, they'll always be Madagascan hissing cockroaches, which are vastly different from cockroaches you'd actually find wherever the setting is, but are available at pet stores. On the rare occasion termites (in the same order as cockroaches) are mentioned, they are invariably confused with ants. In African settings, their large mounds may feature, but typically only as scenery, without the insects themselves featuring.
• A Slaying Mantis (order Mantodea) will always be Mantis religiosa, the "common" praying mantis, and not any of the hundreds of other mantis species.
• Flies (order Diptera) in fiction come in one of three varieties: fruit flies, houseflies, and occasionally huge honkin' biting flies, usually referred to as horseflies. Mosquitoes aren't thought of as flies in fiction, but are still prevalent.
• Wasps and hornets (order Hymenoptera) are usually called "yellow jackets", build nests like paper wasps, and act like hornets. Bees are honeybees or bumblebees, and have hives resembling those of hornets or paper wasps. Ants are common but almost never identified as a specific species. If the ants are a threat to humans, they'll probably be called "fire ants" or "killer ants" (of which there are several species). Parasitic wasps (of which there are thousands of species) are occasionally brought up in horror stories because of their Face Full of Alien Wing-Wong life cycle, but they'll never be identified as a particular species. Tarantula hawk wasps also may occasionally rate a mention thanks to their impressive size and habit of preying on tarantulas.
• Even though everyone calls arthropods "bugs", the order Hemiptera (true bugs) is poorly represented in fiction. The most common ones are cicadas, which are often portrayed as a symbol of summer, especially in Japan and in The Deep South. Aphids occasionally appear as "those little green things that get farmed by ants", and you may get a stink bug as the insect equivalent of a Smelly Skunk. You'll never see, for example, an assassin bug, even though some of the latter (like wheel bugs) make decent rivals to mantises in terms of cool and frightening appearance.
• Fleas (order Siphonaptera) and lice (order Phthiraptera) are often treated as a single species each, but both are made up of a wide variety of species evolved specifically to infest a particular sort of animal, or even particular parts of animals (human head lice and human pubic lice are two different species). The only occasional exception might be if an example is named as a carrier of a specific disease, such as the oriental rat flea for bubonic plague.
• Grasshoppers, locusts, and true crickets (order Orthoptera) are very common, but only generic ones with no species given. If you're really lucky, you might see a katydid, but that's about it. Other members of this order such as mole crickets, cave crickets, wetas, and grigs are unheard of.
• Caddisflies, dobsonflies, and stoneflies (orders Trichoptera, Megaloptera, and Plecoptera) are virtually nonexistent. The exception is stories involving fly-fishing, where the larvae of these insects are often used as lures. In such works, certain types may get mentioned by name, such as salmonflies, fishflies, and hellgrammites. The adults, on the other hand, will never be seen.
• Despite having a trope named after them, mayflies (order Ephemeroptera) are very rare in fiction, and they're never identified to the species or even family level.
• Antlions and lacewings (order Neuroptera) are both uncommon, but antlions — and creatures inspired by them — appear in fiction far more frequently than lacewings do. However, pretty much all pop-culture depictions of antlions are based on their burrowing, predatory larvae, as opposed to the winged adults.

Crustaceans

• There are lobsters, crabs and shrimp (order Decapoda). Crabs are almost always one of hermit crabs, blue crabs, or Alaskan king crabs. Lobsters are typically the familiar species of the genus Homarus (although Animal Crossing: New Horizons and Persona 5 both have spiny lobsters), and to make matters worse, especially in animation, they're bright red (live lobsters are brownish-green; they only turn red when they're cooked). Shrimps are also often colored either pink or orange in advertising, even if they're supposedly alive. In The Deep South or during Mardi Gras in New Orleans, you may encounter crawfish. They will be boiled, bright red and an excellent reason to have a beer (they're very spicy when prepared Cajun-style).
• Decapods are better off than the mantis shrimp (order Stomatopoda), who despite being the living spineless incarnation of badass, almost never appears in books or other works of fiction. When it does, it is always in aquarium books demanding that one kill it on sight, with the notable exception of Fragment, where several of Henders Isle's nightmarish inhabitants are distant relatives of mantis shrimp (in fact, at one point the characters theorize that this is looking at it backwards: that mantis shrimp originated on Henders Isle.)
• Armadillidiids, more commonly known as pill bugs (order Isopoda), are fairly common, but you can bet that nobody will actually refer to them as crustaceans.
• Barnacles (subclass Maxillopoda) are crustaceans as well, but they're usually only shown as "that stuff that covers rocks, ships and whales". Or as being so ugly that everyone died. Speaking of maxillopods in SpongeBob SquarePants, Plankton is likely the only copepod you will ever find in fiction.
• Good luck ever finding an ostracod (subclass Ostracoda).

Myriapods

• The most common members of this subphylum are centipedes (subclass Chilopoda) and millipedes (subclass Diplopoda). These are often referenced in media, but are often much larger than they should be. They are never painted in a positive light, and are often referred to (mistakenly) as insects, or just dismissed as "bugs". As if centipedes and millipedes didn't get it bad enough, other subclasses (Pauropoda, Symphyla) within Myriapoda will NEVER be mentioned.

Chordates (Chordata):

The phylum Chordata contains all vertebrates as well as some more things. It is split into many classes and orders.

Invertebrate chordates (Cephalochordata and Tunicata)

• Invertebrate chordates, including lancelets and tunicates, are unheard of outside of educational works, and even there, they're not common. Sea squirts (class Ascidiacea) are probably the best known of these, but that's not saying much.

Vertebrates (Vertebrata)

Jawless fish (Agnatha)

• Lampreys (order Petromyzontiformes) and hagfishes (order Myxiniformes), occasionally mentioned for their "ick" value, are always lumped under the generic designation of "fish", even though they're less closely related to the two extant jawed fish than you are to these fish. Hagfish, which have variously been considered invertebrate chordates and vertebrates that have lost their vertebrae secondarily (the second theory is currently accepted), never appear except in educational works.

Cartilaginous fishes (Chondrichthyes)

• Sharks (superorder Selachimorpha) are almost always either great whites or hammerheads. Maybe you'll get a tiger, mako, or whale shark, but that's about it outside of more scientific works. Megalodon may appear occasionally if the work is set in prehistoric times (and sometimes even if it's not).
• Rays (superorder Batoidea) are uncommon, especially compared to sharks, and come in two main varieties: manta rays and generic stingrays. Electric rays and sawfish may appear.
• The most represented members of the clade Holocephali are, ironically, probably the extinct Paleozoic fishes Stethacanthus and Helicoprion (both of which are always treated as sharks), and that’s pushing it. Modern chimaeras (commonly known as ratfishes in North America, rabbitfishes in Europe, and ghost sharks in Australia), are unseen except when included in educational works for the sake of completeness (being the third major group of cartilaginous fish).

Ray-finned fishes (Actinopterygii)

What most people think of when they hear the word "fish" — and oftentimes, if a fish is represented in media it will be a generic, very nondescript creature resembling members of this class. Out of the over 30,000 species, relatively few are known to most audiences. In fishing games, there are really no rules, but other popular media stick to the best-known species:

• Sturgeons (order Acipenseriformes) mainly appear as eggs (caviar), which are considered a delicacy for wealthy people. The live form are much less common. Paddlefish are never shown except in a few educational works.
• "Eels" (Anguilliformes) will typically be generic and will often be called "moray eels" even if they more closely resemble other species. Besides anglers, the pelican or gulper eel is probably the most common deep-sea fish — which isn't saying much. The related tarpons (Elopiformes) and bonefishes (Albuliformes) don’t appear despite being popular game fish where they are found.
• Herrings, shads, sardines, and anchovies (order Clupeiformes) will be either food fish or generic background fish.
• The order Cypriniformes is the largest truly monophyletic traditional order of fish, but only domestic goldfish and koi are particularly common. Wild carp are best known as a popular recreational fish in Europe and an invasive pest in North America. The only other cypriniforms you can expect to see are generic "minnows". While many cypriniforms, such as the ide, roach, rudd, and tench, are popular sport fish in Europe; don't expect to see them. Nor can you expect to see such things as barbs, shiners, suckers, or loaches.
• Characins (order Characiformes) are a huge group containing many common aquarium species such as tetras, but the only ones ever seen in fiction are the X-ray fish (by virtue of its name starting with X) and of course piranhas, though the piranha's herbivorous relative, the pacu, will appear in a few educational works.
• Electric eels (Gymnotiformes) are commonly used to add danger in any underwater setting (even saltwater). They’re actually knifefishes, not eels, but they will often be portrayed as true eels except, well, electric. Other knifefishes are not shown at all.
• Catfish (order Siluriformes) are well-known but only semi-common in fiction. They usually do not look like any particular species.
• Pikes (order Esociformes) are sometimes seen as antagonists in freshwater settings, but the related mudminnows never show up.
• Trout and salmon (order Salmoniformes) are typically the go-to freshwater fish in fiction and usually what you see when characters are fishing. Pacific salmon in particular are often seen swimming up streams, jumping up waterfalls, and/or getting eaten by grizzly bears.
• The cod, haddock, pollock, ling, and hake (order Gadiformes) are more common as food than as living fish.

Percomorphs (clade Percomorpha)

• Percomorpha contains about half of all bony fishes and naturally includes many of the common fishes seen in popular culture. Many, but not all, fishes in this group are traditionally classified under the order Perciformes, though this order as traditionally defined is not monophyletic. Some of the better-known recently-defined orders are listed below:
  • Scombriformes. Tuna (and to a lesser degree mackerel) generally appear in the form of food for humans, but live ones are a semi-common choice for large pelagic fish. Escolars, butterfishes, and driftfishes are never mentioned or shown at all.
  • Syngathiformes. Seahorses are very common, and are often portrayed as acting like horses. The leafy seadragon and mandarin dragonet are the only representatives of their families and are even then restricted to educational works. You are quite unlikely to see a pipefish, seamoth, trumpetfish, or cornetfish.
  • Anabantiformes. Siamese fighting fish (bettas), paradisefish, and kissing gouramis sometimes appear as aquarium fish, though nowhere near as often as goldfish. Snakeheads, best known as an invasive fish in the mid-Atlantic US, have been featured in at least a few monster B-movies. Climbing perches and ctenopomas are unheard of.
  • Perciformes (in the current stricter sense). Perch are generally shown in the context of game fish. Groupers, snappers, and sea basses are generally shown as seafood. Members of the order Scorpaeniformes are now often included here; the best known of these are the lionfish, although the blobfish will occasionally be noted for its unfortunate appearance (which is actually a result of tissue damage and being crushed by the pressure from being taken onto land; it will be never shown in its natural form). Rockfish, sculpins (besides the blobfish), and icefish have excruciatingly scarce representation in popular culture, and other species, such as wrymouths, combfish, and searobins, have none at all.
  • Centrarchiformes (often included in Perciformes). The best known species of this order by a large margin are freshwater sunfishes (including black basses, crappies, and the bluegill), which generally appear in the context of sport fishing. The many other members of this order, including the Australian and Asian perches, grunters, sea chubs, hawkfishes, and the old wife, are never seen at all or only as background animals.
  • Cichliformes. The best known members of the cichlid family are tilapias, and always as food, to the point where some think that tilapia are not naturally occuring. While many species of cichlids are popular aquarium fish, they very rarely appear in fiction. Clownfishes have become popular due to Finding Nemo, but other damselfishes are not commonly represented anywhere. There is one appearance each of a basslet (Finding Nemo) and a convict blenny (The Octonauts) in popular media.
  • Lophiiformes. Deep-sea anglerfish are by far the most common deep-sea fish. Good luck looking for shallow-water species such as goosefish, frogfish or batfish, though.
  • Acanthuriformes. Most tropical fish depictions appear to be some sort of angelfish, butterflyfish, or tang. The regal tang has become popular due to Finding Nemo The Moorish idol and the rabbitfishes are less common, and the sicklefishes, boarfishes, and louvar are nonexistent.
  • Tetraodontiformes. Puffers appear often, but triggerfish and boxfish have no such luck and are much less common. The largest of all bony fish, the ocean sunfish, mostly appears in Japanese media (mainly due to its historical and culinary relevance), despite the species being found in oceans around the world.
  • Beloniformes. Flying fish are well-known but not very common in fiction. However, they are more fortunate than their relatives, like halfbeaks or needlefish, who never appear at all.
  • Carangiformes/Carangaria. Billfishes are fairly common saltwater predators, usually a swordfish or a blue marlin. The sailfish might get a mention in documentaries due to it being the fastest fish in the world. Barracudas are less common, but they may serve as a marine equivalent of pike. The archerfish may appear in educational works thanks to its unusual "shooting" ability. Remoras, or sharksuckers, were once nonexistent in the media but have become more well-known thanks to their appearing in such works as Pokémon and The Magic School Bus. Moonfish are only known from Finding Nemo. The dolphinfish (popularly known as the “mahi-mahi”) and the jacks are very uncommon and even then are primarily known as food fish. Flatfishes such as plaices, halibuts, and soles (Pleuronectiformes, cladistically included within Carangiformes) are also mainly recognized for their culinary significance, though generic flounders appear fairly commonly alive by virtue of their distinctive appearance.

Lobe-finned fishes (Sarcopterygii)

• The best known sarcopterygian is the West Indian Ocean coelacanth (Latimeria chalumnae, order Coelacanthiformes), known (inaccurately) as living fossils. However, it rarely shows up in fiction. Generic coelacanths are the standard fish in prehistoric settings, but that's if they aren't just generic fish altogether.
• Lungfishes (order Dipnoi) are seen only in educational works.
• Stem-tetrapods or "fishapods", in particular Eusthenopteron, Icthyostega, and more recently Tiktaalik, are common in educational works but otherwise rare.

Tetrapods (Tetrapoda)

Amphibians (Amphibia)

• Temnospondyls (order Temnospondyli) get an occasional nod in Lost World adventure-fiction, but that's about it. On the rare occasion that a specific taxon is mentioned, it’ll invariably be Eryops. Diplocaulus may show up as well thanks to how weird it looks, but it's unlikely to be mentioned by name.
• Good luck finding a caecilian (order Gymnophiona).
• Salamanders and newts (order Urodela) are less common than frogs, but when they do appear, they're given any color and pattern. The axolotl, a Mexican salamander with external gills, has gained some popularity in recent years, and will always be leucistic.
• Frogs and toads (order Anura): “Frogs” will usually be green and look like bullfrogs but go "ribbit" like Pacific tree frogs. “Toads” will be generically brown, squat, warty, and unidentifiable by species. For a more exotic setting, red-eyed tree frogs and poison-dart frogs are popular.

Lepidosaurs (Lepidosauria)

• The Tuatara, the only living member of the order Rhynchocephalia, only appears in educational media and New Zealand works.
• The order Squamata is common in fiction.
  • The most common lizards you'll see on TV/movies are generic lizards, iguanas, chameleons, geckos, and the occasional frilled lizard (if it's set in Australia). You might see a monitor lizard every now and then, particularly the Komodo dragon. Gila monsters show up occasionally. Note that if an iguana does show up, it will almost always be a palette-swapped chameleon or Gila monster, sporting a projectile tongue, color changing abilities and a taste for bugs and small animals. Herbivorous real world iguanas display none of these traits.
  • Snakes (which are technically derived lizards) in fiction come in five main styles: cobras, rattlesnakes, constrictors (pythons, anacondas, and smaller boas being the most popular), and "generic deadly" (which are often represented by corn snakes, which superficially appear appropriately dangerous) are the first four. The fifth type of snake is "generic harmless", usually a green garden snake or a garter snake (you might see a kingsnake every now and then). Somewhat averted in Australian fiction, if only due to the sheer number of venomous snakes available. The cobra species you'll most commonly see is Naja naja, the Indian cobra. That's because it's the "snake-charmer" cobra. The king cobra (Ophiophagus hannah) is larger, but a proportionally smaller hood, thus making it less "evil" in appearance.
  • Amphisbaenians (often considered separate from lizards despite the fact that they are cladistically lizards, which makes their nickname of "worm-lizards" incidentally correct in a way) are rarely mentioned even in documentaries.

Turtles and kin (Testudines)

• The vast majority of testudines in fiction are either sea turtles or tortoises. You might see a snapping turtle, red eared slider, or a softshell if you're lucky.

Archosauromorphs (Archosauromorpha)

• Tanystropheus (order Protorosauria) occasionally appears in documentaries as "that Triassic reptile with a ridiculously long neck". Other protorosaurs never show up, even in documentaries.
• Basal archosaurs (obsolete order Thecodontia) only appear in more educational or scientific works. Besides Postosuchus in Walking with Dinosaurs, the only one you are likely to see is Euparkeria due to its historical status as "the ancestor of the later archosaurs".

Archosaurs

• Pseudosuchia (crocodilians and their prehistoric relatives):
  • When people think of crocodilians (order Crocodilia), they're most likely going to picture a generic green "alligator" or "crocodile". In cartoons, they are not usually depicted as any particular species, and when a specific species is used, it is typically the American alligator, the Nile crocodile, and the saltwater crocodile, depending on the setting. Rarely will you see a gharial or a caiman in non-documentary media.
  • Prehistoric crocodylomorphs were very diverse, and included everything from ranging from marine taxa with limbs and tails turned into fins, to freshwater forms, to terrestrial and possibly warm-blooded crocs such as sphenosuchians and notosuchians of various size and diet (the latter ranged from carnivores to omnivores and possibly even herbivores). Yet in fiction prehistoric crocodylomorphs are always just generic oversized versions of living crocodilians, and pretty much the only specific prehistoric crocodylomorph you can expect to see is Deinosuchus (which is a true crocodilian). It's possible to find Sarcosuchus or some other large species in a documentary or two.

• Birds (Aves, or Avialae) are the only living dinosaurs: Archaeopteryx, is the classic “dino-bird” and can be considered fairly common, at least for Mesozoic birds (educational works might throw in Hesperornis, Ichthyornis Confuciusornis and/or enantiornithines “opposite birds”, but don't hold your breath). Few extinct Cenozoic birds are ever used — not even the rather awesome elephant bird or the formidable pseudotoothed birds. The exception to this is the dodo which is practically a symbol for 'extinction', and has a reputation for being Too Dumb to Live. Occasionally also the terror birds, namely Phorusrhacos or Titanis. Gastornis (long thought to be predatory, but now known to have eaten fruits and seeds) may show up as well. Educational works might throw in the great auk, passenger pigeon, the moas, and maybe a handful of others mentioned below.
• You will never see members of certain obscure bird orders, such as the hoatzin (order Opostocomiformes), the cuckoo-roller (order Leptosomiformes), mousebirds (order Coliformes), mesites (order Mesitornithiformes), or the sunbittern and kagu (order Eurypygiformes)
• Ratites (unranked clade Paleognathae) are typically the common ostrich (Struthioniformes). Other species are typically only shown in region-specific works of fiction; expect kiwi (Apterygiformes) in New Zealand works, the Emu (Casuariformes) in Australian works, and very rarely the greater rhea (Rheiformes) in works set in southern South America. Cassowaries (Casuariformes), specifically the southern cassowary, are becoming more popular due to their dangerous reputation, though they are still relatively rare. The flighted tinamous (Tinamiformes) of South America are entirely unrepresented.

Fowls (Galloanserae)

• Ducks (order Anseriformes) will usually be mallards (wild or domestic) and geese will usually either be Canada geese or grey geese (usually domestic). And of course there's swans, which are always mute swans, and always pretty and gentle, even though mute swans are very territorial and will chase after and attack a human without hesitation. The black swan may appear, but (outside of Australian works) typically just for the sake of the metaphor. Also, when Canada geese show up, they will almost always be called Canadian geese. The great diversity of fossil anseriforms (including the giant ratite-like dromornithids that coexisted with early Australian Aboriginals) is never acknowledged.
• Landfowl (order Galliformes) are typically represented by the domestic chicken and turkey. The Indian Peafowl is quite commonly depicted, although they will almost always be males (peacocks). Wild galliforms such as grouse, quail, pheasants, and partridges tend to be confused with each other (which is just as well considering that some of these groups are not even monophyletic), and they are most likely to appear as food. However, the partridge will probably get a mention at Christmastime thanks to "The Twelve Days of Christmas". Guineafowl (Numididae) are quite rare, and they will always be the Helmeted species (except in The Lion King (1994), where they were Vulturine Guineafowl). Members of the families Megapodidae (scrubfowl, brushturkeys, and the malleefowl) and Cracidae (chachalacas, curassows, and guans) are never seen, except for Disney's Aracuan Bird, who is supposedly an East Brazilian Chachalaca (Ortalis araucuan) but does not resemble one in the slightest.

Neoavians (Neoaves)

• The only notable grebe (order Podicipediformes) is an entirely fictitious species (the "Green-tailed Grebe" in Arthur).
• Flamingos (order Phoenicopteriformes) are quite often the plastic lawn variety, and even if they aren't, will be uniformly bright pink. They tend to be treated as one species in fiction.
• Bustards (Otidiformes) never appear, despite their wide range and including some of the largest flying birds.
• Pigeons (order Columbiformes) in fiction are for the most part limited to the common rock pigeon, generic white doves, the occasional turtle or mourning dove, and the extinct Dodo (although the passenger pigeon is a staple of educational works on extinct animals).
• Sandgrouse (order Pterocliformes) are scarce even in educational works; one appeared in The Cat in the Hat Knows a Lot About That!.
• The only cuckoo (order Cuculiformes) that often appears in fiction is the Common Cuckoo, which is the one that makes the distinctive sound the order is named for (which is replicated in cuckoo clocks). Thanks to Looney Tunes, roadrunners are also relatively well-known, but they don't commonly appear elsewhere.
• Turacos (order Musophagiformes) have a very small handful of appearances: The Go-away-Bird (White-bellied Go-away-bird) 3rd & Bird, and The Lion Guard (both great blue turacos).
• The most represented members by far of the clade Strisores (classified either as one order or as many as six or seven) are generic hummingbirds, which are fairly common in tropical and subtropical settings. Frogmouths only appear in Australian media; as such, they will specifically be the tawny frogmouth. The whip-poor-will and other nightjars are often heard but never seen, which is pretty much the case in reality. Neither will you see (or hear, for that matter) swifts, owlet-nightjars, potoos, or the oilbird.
• Aside from cranes (which are often confused or conflated with herons and storks), the order Gruiformes is essentially nonexistent in fiction, with things like rails, flufftails, and finfoots being just as elusive in fiction as in real life.
• In fiction, the order Charadriiformes is generally restricted to gulls (which will invariably be called seagulls), puffins, generic shorebirds, and historically the Egyptian Plover (as "that bird that eats crocodile scraps") and the extinct great auk. When penguins are prominently featured, skuas may appear as antagonists. Educational works might throw in the Arctic tern (for its record-breaking migration) or certain North American plovers (for their conservation relevance).
• Even though everything's better with penguins (order Sphenisciformes), they are usually either emperor penguins or adelie penguins (the two well-known species of Antarctica). Assuming, that is, they're shown as a specific species rather than the generic cartoon version with yellow or orange beaks and feet. Every now and then you will see a macaroni or rockhopper penguin, due to their distinctive head tufts. They will almost always be shown desiring a frigid cold environment, despite many species being found in temperate and even tropical beaches.
• The calls of loons (order Gaviiformes) are common in all wilderness settings, but the birds themselves rarely appear, and typically just in works set in Canada, Minnesota, or northern Europe (the natural geographic range of these birds).
• Albatrosses (order Procellariiformes) occasionally show up in maritime-oriented works. Shearwaters, petrels, and storm-petrels, also in this order, are never depicted.
• The best known members of the order Suliformes (formerly lumped with Pelecaniformes) are the boobies, which will appear solely to invoke Heh Heh, You Said "X", and will always be the Blue-footed variety for extra humor. Cormorants, frigatebirds, and darters virtually never show up in fiction except as background wildlife.
• Storks (order Ciconiiformes) almost only appear in reference to delivering babies, unless they are Marabou Storks, which used to be semi-common in works set in Africa.
• Pelicans are easily the most familiar members of the order Pelecaniformes. The other members, which were formerly in Ciconiiformes, are less familiar but still appear sometimes. The Shoebill, often incorrectly referred to as the "shoebill stork", has become famous in Japan since its debut in zoos there, due to its comically menacing appearance, and in recent years has made several appearances in anime and games. The related Hamerkop has only appeared once, in The Lion Guard. Herons appear with some frequency, usually as background birds in wetland settings. Don't expect to see ibises or spoonbills. When ibises do appear, it's generally in the following 3 circumstances; the Scarlet Ibis in the tropical Americas, the Australian Ibis ("bin chicken") in the context of an Australian urban setting and feeding on garbage, and the African Sacred Ibis in the context of Ancient Egypt.
• The sister orders Accipitriformes and Cathartiformes (both formerly lumped with Falconiformes, and the latter previously also included in Accipitriformes and Ciconiiformes) tend to be represented by generic vultures (invariably circling over something dead or dying unless in an alphabet book), hawks (which are either generic, red-tailed hawks, goshawks, or common buzzards) or bald and golden eagles. All of them will likely sound like red-tailed hawks. The Andean and California Condors, the Osprey, the Harpy Eagle, the Philippine Eagle, and the secretarybird are the only other species that appear with any regularity. Don't expect to see more obscure species, even the more spectacular ones like the king Vulture, the swallow-tailed Kite, or the changeable hawk-eagle.
• Speaking of the Falconiformes, you'll rarely see a falcon that isn't a peregrine, especially if it's wild; they're well-known to many people as the fastest flying bird (faster than the cheetah) and a symbol of successful conservation efforts. Other falcons like kestrels, sakers, and caracaras are less well-known.
• If an owl (order Strigiformes) appears and it's not generic, expect it to be either a snowy owl, great horned owl, or barn owl. Other species like screech-owls, scops owls, pygmy owls, the burrowing owl, or the Eurasian eagle-owl, are typically either ignored or just marketed as up-scaled generic owls.
• The (resplendent) quetzal (order Trogoniformes) is fairly common in alphabet books instead of "quail". Other trogons never appear.
• The laughing kookaburra (order Coraciiformes) is known for precisely two things: that one children's rhyme and its cry, which is often attributed to a monkey. Other kingfishers only appear as background wildlife. The amazingly colorful bee-eaters never appear.
• The order Bucerotiformes was formerly grouped with Coraciiformes. The Lion King (1994) has the only notable appearance of a bucerotiform in fiction (Zazu the hornbill). While the Eurasian Hoopoe is somewhat well-known in the Middle East and Mediterranean Europe, it makes only occasional appearances in popular culture.
• The order Piciformes is represented by woodpeckers, toucans and very occasionally the honeyguide (the bird that leads hunter-gatherers and allegedly badgers to honey). Woodpeckers are often depicted in a generic way, with red (sometimes crested) crowns and black and white patterns that may or may not match any real-world species. A coppersmith barbet appears in The Jungle Book. Don't expect to see jacamars, puffbirds, or nunbirds.
• You would expect that seriemas (Cariamiformes), being the only surviving relatives of the famous terror birds would give them at least a bit of media attention, but this is most certainly not the case; they virtually never appear in fiction.
• Parrots (order Psittaciformes) are often represented as generic, brightly-colored birds able to talk fluently. New Zealand parrots (the kea, kakapo, and New Zealand kaka) only appear in some New Zealand works. Cockatoos are uncommon: they are typically the large white ones such as the sulphur-crested. The cockatiel and galah do appear sometimes in Australian works, and other species, such as black cockatoos and the smaller white cockatoos, aren't seen at all. Typical parrots are usually macaws, and even then, it's almost always the Blue-and-gold Macaw or Scarlet Macaw. Blue macaws have one notable appearance, and the small macaws are nonexistent. Gray parrots or Congo African greys hold some popularity since Alex. Small "parakeets" are usually represented by the Budgerigar. Any sufficiently tropical location may have lorikeets, either Green-Naped or Rainbow. Many other parrot species, such as conures, Pionus parrots, amazons, lovebirds, and the Rose-ringed Parakeet, are rare to nonexistent in popular media despite many being fairly common pets.
• Perching birds (order Passeriformes), the largest bird order, are quite poorly represented. These are often generic songbirds, sometimes named as "sparrows" or "finches". The term "blackbird" is often applied to a generic bird that may be a corvid, a starling, a Eurasian blackbird, a grackle, or some combination of these. Canaries are common as pets, and the barn swallow is well-known in many regions of the world due to its immense range.
  • Members of the Corvus genus are often treated as either two species (the "crow" and the "raven") or one species. You might find a rook or Eurasian jackdaw in some poetic European works. Other corvids are represented by magpies (always the black-and-white ones found in North America and Eurasia), the blue and Steller's jays in North American works, and less commonly the Eurasian jay and red-billed chough. Treepies, nutcrackers, other jays, and the green and blue magpies are ignored.
  • The distantly related Australian magpie is the most common songbird in Australian works, but that's not saying much. Some other Australasian songbirds, such as bowerbirds, birds-of-paradise, lyrebirds, fairy-wrens, and Australasian robins, either are never shown or only appear in educational works.
  • Speaking of robins, both the American robin (a thrush) and the European robin (an Old World flycatcher) are quite common, but the birds (which are only somewhat closely related) are often confused with one another, causing several cases of misplaced birdlife.
  • European works may feature wagtails, great, Eurasian blue, and willow tits, house and Eurasian tree sparrows, the European starling, the Eurasian wren, the European goldfinch, and the Eurasian bullfinch.
  • North American works may feature bluebirds, chickadees, the northern mockingbird, the northern cardinal; and less commonly, wrens, the Baltimore oriole, and the American goldfinch. Most of the various tropical American passerine groups are unseen in popular culture, with the exception of the umbrellabirds due to their place of importance in “animal alphabet” media.
  • The common myna is fairly common in Indian and Southeast Asian works, and the related Bali myna appears in a few educational works. The closely related oxpeckers are the most common passerines in works set in Africa, but they are usually portrayed as generic birds. Besides them, the only African passerines that appear with regularity are weavers. Sunbirds appear with some frequency as background birds in works set in the tropics, but they are often confused with the unrelated hummingbirds.
  • The birds mentioned above barely scratch the surface of passerine diversity; in popular media, you will never see accentors, antbirds, broadbills, bushshrikes, crescentchests, cupwings, elapaios, flowerpeckers, gnatcatchers, grassbirds, hyliotas, the hylocitrea, the hypocolius, laughingthrushes, manakins, nicators, pittas, the rail-babbler, rockfowl, rockjumpers, the sapayoa, seedeaters, silky-flycatchers, spindalises, sugarbirds, tanagers, tityras, vireos, or whydahs. Even the Tyrannidae, the largest family of birds, are unheard of, except for the scissor-tailed flycatcher (the state bird of Oklahoma). Don't even expect to see the red-billed quelea, the most populous wild bird, except in educational works.

Mammals (Mammalia)

• While all groups of organisms are prone to this trope, mammals seem to have one of the greatest diversities in fiction, which may have something to do with the fact that they include humans.
• One the whole, all extinct mammals that aren’t woolly mammoths or sabre-toothed "tigers" that show up are simply generic shrew-like creatures that get eaten or crushed by dinosaurs, and that's only if they're lucky. They may also be shown as survivors of the Cretaceous-Paleogene extinction.
• Good luck trying to find any non-therian (Theria is the group of mammals that includes placentals and marsupials) mammaliaforms outside of the still-living monotremes. Dinosaurs coexisted with a number of groups over the course of the Mesozoic, including morganucodonts, docodonts, multituberculates, gondwanatheres, eutriconodonts, and the large◊ herbivorous mesungulatids; and a few of these now-extinct clades became quite successful in the early Cenozoic. Only in a handful of educational works, such as Dinosaur Revolution and Dinosaur Train, are these forms specifically acknowledged.

Monotremes

• The platypus (family Ornithorhynchidae) is the only monotreme showing up in fiction. The hedgehog-like echidnas (family Tachyglossidae) are rarely (if ever) heard of, even in documentaries. An exception is made for fiction in which Australia is the main location. Or in the Sonic fandom.

Marsupials

• Despite having more than 300 species, the amount of Marsupials used in fiction could be counted on a few fingers. Kangaroos and koalas (order Diprotodontia) are obviously the most popular, and instantly come to mind at the word "marsupial". Every now and then, you'll see a wombat, wallaby, or sugar glider (a handful of others show up in Australian works). Don't expect to see fossil members of this order, even the more impressive ones like the giant short-faced walking kangaroo Procoptodon, the rhino-sized wombat-like Diprotodon, and the carnivorous cat-like "marsupial lion" Thylacoleo, outside of documentaries.
• The only bandicoots (Paramelemorphia) in fiction are Crash Bandicoot and his companions. The only two bilbies in fiction are the titular characters of Bilby and Boj. Mention should be made, however, of an Australian substitute for the Easter Bunny, the "Easter Bilby".
• The only opossum (Didelphimorphia) ever portrayed in fiction is the Virginia opossum (which is often called a possum despite that term becoming applied to some Australasian marsupials) — there are apparently close to 100 opossum species ranging from the semi-aquatic yapok to primate-like woolly opossums to mouse opossums with no pouches. Aside from the true opossums there are two other orders of marsupials in the Americas: the shrew opossums (order Paucituberculata) and the Monito del Monte (order Microbiotheria), each more closely related to Australian marsupials than to true opossums.
• The best-known carnivorous marsupial (order Dasyuromorphia) is the Tasmanian devil — although, thanks to the cartoons, most non-Australians apparently believe it isn't real. Of course, those cartoons do inaccurately portray it as bipedal, able to spin in a circle really fast, and capable of muttering semi-intelligible gibberish. The extinct thylacine (Tasmanian tiger) appears in some Australian works. Other dasyuromorphs, such as quolls, dunnarts, planigales, and the kowari are either nonexistent or appear in a small handful of Australian works.

Placentals

• Living armadillos (order Cingulata, formerly lumped with Pilosa as Xenarthra or Edentata) if not generic, are generally Nine-banded Armadillos, which are associated with the American southwest despite other species being found only in Central and South America. Additionally, all armadillos will be portrayed as being able to roll up, even though only the two species of three-banded armadillos are capable of this. Glyptodonts (now considered to be derived armadillos) are relatively popular for prehistoric mammals. Don't expect to see a pampathere, though.
• The order Pilosa (formerly lumped with Cingulata as Xenarthra or Edentata) is represented by three-toed sloths and the Giant Anteater. Tamanduas (lesser anteaters) and two-toed sloths are very rarely shown, and the Silky Anteater is completely missing. Extinct pilosans will always be ground sloths, usually the giant Megatherium or occasionally the bear-sized Megalonyx.
• Elephants (order Proboscidea) are nearly always African in cartoons, because big ears are funny. They're nearly always Asian in movies or on TV, because they're the only ones you can actually have on set. Outside the Discovery Channel, all extinct proboscideans are mammoths or mastodons and almost all mammoths are woolly (you might see a Columbian mammoth in every now and then). Deinotherium, Platybelodon, and Moeritherium are the only other extinct proboscideans prevalent in works about extinct Cenozoic mammals, and even then that's pushing it. Expect elephants (and only elephants) to be called "pachyderms" even though this has been obsolete for a century, and contained more than just elephants.
• Other than elephants, Tubulidentata (containing only one living species, the Aardvark) is probably the most commonly shown afrotherian order in fiction, with Sirenia (manatees and dugongs) a distant third. The other orders; Macroscelidea (sengis or elephant-shrews), Afrosoricida (tenrecs, otter-shrews and golden moles), and Hyracoidea (hyraxes); are nearly never seen unless the work intentionally features seldom-seen species, and the various fossil groups have zero representation. Note that tenrecs in popular culture outside of the Wild Kratts episode are always the Lowland Streaked.
• Rodents (order Rodentia) are not very diverse in fiction, which is especially odd as the rodents are the largest of the mammal orders, with 40% of mammal species in it. Many rodents seem to be conflated together to form some sort of new creature.
  • The best known members of the (suborder Castorimorpha) are by far the two species of beaver (Eurasian and North American). Gophers (properly known as pocket gophers) are well known as pests in lawns and golf courses, but they are often depicted like ground squirrels (pocket gophers have external cheek pouches, larger claws, smaller eyes, bare tails, and are more fossorial and mole-like overall). Kangaroo rats are sometimes shown in North American desert settings, but the related pocket mice have only appeared once in popular media (a children's song) despite their scientific importance.
  • Mouse-like rodents (suborder Myomorpha) are generally represented by standard mice and rats (typically the House Mouse and Brown Rat), hamsters and gerbils (as pets), and lemmings (always jumping into the sea since White Wilderness). Mice and rats are commonly confused, specifically House Mice and Brown Rats (the latter of which are ALWAYS diseased and filthy in fictionland, unless they're pets. Even some pet ones are depicted this way). Often you see a character screeching and screaming or going "yuck" and calling what is often a House Mouse a rat. You also have the people who call every myomorph rodent a rat — unless casting requires the opposite, as when the unambiguous Brown Rat in Because of Winn-Dixie is repeatedly described as a "mouse". Unfortunately, this is Truth in Television for many. Never mind the fact that the words are not applied consistently anyway (pocket mice are closer to kangaroo rats than to the House Mouse, and pack rats are closer to deer mice than to the Brown Rat). Similarly, guinea pigs are constantly confused with hamsters, even though they hardly look alike and are only very distantly related (hamsters are closer to mice and rats, while guinea pigs are closer to porcupines.) Google either and you will eventually see hamsters in the guinea pig search, and guinea pigs in the hamster search. They are usually depicted with running wheels, salt licks, and seeds, when all three of these are extremely unhealthy and even dangerous for guinea pigs. Guinea pigs are also often drawn the size and shape of the more familiar hamsters, and only called guinea pigs for plot reasons (such as they are being experimented on, or the creators thought "guinea pig" sounded cooler/more mature/wanted to avoid being connected to Hamtaro). When a North American native rodent is shown, it will be a Muskrat, a meadow vole, a deer mouse, or, for the sake of the metaphor, a pack rat (these will generally be depicted in a generic way).
  • Jerboas appear very occasionally. Bamboo rats have one very brief, non-notable appearance in Sofia the First. You won't find African climbing rats, birch mice, mole voles mouse-like hamsters, vesper rats, rice rats, or the Malagasy Giant Rat.
  • Porcupine-like rodents (suborder Hystricomorpha) are represented by, of course, porcupines (typically the North American or Crested varieties) and guinea pigs (though, as stated before, these are usually guinea pigs in name only, as they are conflated with hamsters). For a while capybaras were rare in non-educational works, but eventually started to appear (mainly in Japanese works) starting around The New '10s. The chinchilla rates an occasional mention, either as somebody's coat or somebody's faddish pet. It's not uncommon for chinchillas to be treated as rabbits or mice. The unique naked mole-rat is quite rare, with one notable appearance (Kim Possible). Blesmols ("regular" mole-rats) also have one (The Lion King). Degus, despite being kept as pets, are nearly unheard of in fiction. Agoutis only show up in educational works for their relationship with the Brazil nut tree. Never expect to see tuco-tucos, maras, pacas, cane rats, hutias, or the Dassie Rat.
  • As for the various forms of squirrels (suborder Sciuromorpha, family Sciuridae), tree squirrels (usually simply called squirrels) are the most common, followed by chipmunks in American and Japanese works, and, on occasion, flying squirrels. Prairie dogs occasionally appear in works set in the Great Plains. The only marmot that appears with any regularity is the groundhog, and almost always in connection with Groundhog Day. Out of the tropical squirrel species, none appear in fiction, and only one (the Indian Giant Squirrel) makes notable appearances in popular culture at large. Dormice (Gliridae), which are the closest relatives to squirrels, will always get treated as mice. The Mountain Beaver is never shown.
• Rabbits (order Lagomorpha) sometimes get lumped in with rodents, but this is wrong. If you see a lagomorph, it's probably going to either be a standard cottontail, European Rabbit, or white domestic rabbit if it's a rabbit; or a jackrabbit or Brown Hare if it's a hare. "Rabbit" and "hare" will often be treated as synonymous (though some rabbits are closer to hares, hares are highly derived and distinctive leporids). Hardly anyone ever talks about pikas in fiction, unless it is joined to a '-chu'.
• Primates (order Primates) have a wide variety:
  • In comics, animation, and other cartoon-based works, "monkeys" are frequently a generic variety that's a bit like a rhesus macaque with darker fur or a young chimpanzee with brown fur and a tail, regardless of their ostensible species or place of origin. Any non-human simians may be referred to as monkeys (which, if treated as a monophyletic classification, could be an acceptable term for any simian, though that would ironically mean humans are monkeys too). Expect "ape", "monkey", and "chimp" to be used interchangeably, sometimes even within the same sentence.
  • Among the true apes, apart from humans (since we show up by default), we have gorillas, orangutans, and chimpanzees. There are no bonobos (pygmy chimpanzees, the closest relative to the common chimpanzee), though — except in one Humon comic. Also, although there are two species of gorillas and three species of orangutans in real life, in non-educational works they both tend to be treated as a single species. Almost no gibbons appear either, even though these "lesser apes" make up the majority of extant ape species.
  • Apart from the generic monkeys mentioned above, the most frequently seen Old World monkeys are baboons (usually conflated with mandrills, resulting in hybrid creatures with colorful noses and long tails), followed distantly by macaques, which are among the most widespread and diverse primates. Most other Old World monkeys hardly ever show up.
  • If someone has a pet monkey, it will almost always be a capuchin, even in fiction set in Africa or the Middle East (capuchins, like all monkeys with prehensile tails and sideways nostrils, are New World monkeys — that is, only native to the Americas). Besides capuchins, spider monkeys are the best known and most seen New World monkeys, while tamarins, howlers, and marmosets are very rare in media. The uakari is very notable, but (like the umbrellabird) only due to alphabet books and songs. You can forget about night monkeys, titis, and sakis.
  • Don't expect to see non-simian primates much. If a lemur shows up, it will usually be of the ring-tailed variety (although you have a slim chance of seeing an aye-aye, especially in educational works, and sifakas are becoming popular thanks to Zoboomafoo). Works set in Africa occasionally mention galagos (also known as bushbabies). Tarsiers are very occasionally shown. Lorises (specifically the slow lorises) are recently becoming more popular, but the related pottos are out of luck.
  • Extinct non-human primates are represented by Gigantopithecus (closely related to the orangutan and occasionally cited as a possible ancestor of Bigfoot, Sasquatch, and Yeti) and occasionally generic primitive primates (typically based on adapiforms or plesiadapiforms). Early human-relatives are usually come in two variants, the more primitive ape-man that can represent anything from Australopithecus to Homo erectus, and the Neanderthal. Don’t expect to see megafaunal lemurs like the gorilla-sized Archaeoindris or the strange-looking “koala lemur” Megaladapis in non-educational media, even though both died out less than 2,000 years ago. Even in paleodocumentaries, they seldom appear.
• Colugos (order Dermoptera) and treeshrews (order Scandentia) are never shown; never mind that they're our closest living relatives besides other primates.
• Bats (order Chiroptera) usually come in three standard forms in fiction. You've got your standard insect-eating bat, your cute flying fox or fruit bat, and your creepy vampire bat. They will typically be depicted the same. Don't expect to see the sucker-footed, bent-winged, frog-eating, bulldog, or wrinkle-faced bats anytime soon, even in a documentary. Like with rodents, this is especially insulting as bats are a very diverse group, containing 20% of mammal species. They'll sometimes be referred to as rodents, despite being more closely related to the carnivorans, pangolins, and ungulates.
• "Insectivores" (order Eulipotyphla, formerly lumped with Afrosoricida, Macroscelidea, Scandentia, and/or Dermoptera as Insectivorai or Lipotyphla) are represented by generic moles, shrews, and hedgehogs. While hedgehogs are native to the Old World and thus common in folklore and popular culture there, hedgehogs are less prevalent in North American works (but still occasionally appear in North American forest settings) and the most popular hedgehog there is blue. Hedgehogs and porcupines, despite being completely different in many ways, are often confused just because they both have quills. Moles tend to look like the common black European or Eastern moles, though star-nosed moles are getting popularity in recent years. Don't expect to see more unusual eulipotyphlans such as moonrats, desmans, or shrew-moles; or the other members of the Insectivora who got booted out (see above).
• The order Carnivora is prevalent in fiction.
  • Cats (Felidae) are typically domestic or big cats. Since the domestic cat is one species (Felis catus), all breeds count. Big cats (Pantherinae) are fairly well-known and well-represented; you have the tiger, the lion (specifically African lions, good luck finding an Asiatic lion in fiction), the leopard (usually the African leopard, though you might see an Indian leopard every now and then), the jaguar (which will often be mistaken or conflated with leopards and/or cheetahs), occasionally the snow leopard (often lumped in with the just plain leopard despite not being the same species), and even more rarely the two species of clouded leopards. Melanistic (i.e. black-furred) big cats will usually be referred to as "panthers" and treated as a species. Small wild cats (Felinae) are not so lucky; the most common ones are the cheetah and the cougar or mountain lion, both of which are often treated as "big cats". All four species of lynx (Canada, Eurasian, Iberian, and bobcat) have appeared from time to time, though the Iberian is much rarer, with just 2 notable appearances (Zoo Tycoon 2 and The Missing Lynx). The ocelot and the European wildcat are the only other small wild cats that appear with some regularity. You will never see species like the kodkod, Pallas's cat, flat-headed cat, or fishing cat, except in an extremely small handful of zoological works. If it's set in prehistory, the only felids that tend to appear in non-educational works are saber-toothed cats, often called "saber-toothed tigers", despite being in an entirely different subfamily from tigers or any living cats. If the species is ever specified, it will be Smilodon, just one of many saber-toothed cats known from the fossil record. Cave lions may appear in media, usually educational, set in Stone-Age Europe. Speaking of educational media, American lions (close cousin to the cave lion, the saber toothed-cats Homotherium (sometimes called the "scimitar-toothed cat") and Deinofelis (which has a reputation for killing human ancestors), and the American "cheetah" Miracinonyx may be acknowledged in paleo documentaries and the like, but even that's stretching it. Among domestic cats, black and white cats and tabbies seem to be favored in film or in animation. Black cats are specifically seen in anything related to Halloween. "Torties" and solid gray/blue cats are more rare. Siamese or white Persians appear when the cat is intended to be glamorous and/or a villain's. Also see Cat Stereotype.
  • Besides the meerkat, mongooses (family Herpestidae) are essentially known in fiction solely for their cobra-killing reputation, and are sometimes even called weasels. Meerkats are now the best-known species thanks to The Lion King (1994) and Animal Planet, and have overshadowed the over 30 other mongoose species, which tend to be treated as one.
  • Malagasy carnivorans (Eupleridae) are nearly unheard of thanks to lemurs stealing the spotlight; the most popular one is the lemur-eating fossa (several of which appear in Madagascar), but even that's pushing it. Good luck finding a ring-tailed vontsira or a fanaloka outside of All Hail King Julien.
  • Civets, genets and binturongs (Viverridae) are extremely rare in fiction. At best, you might get a reference to the Asian palm civet, a.k.a "that animal that poops coffee beans".
  • Hyenas (which are actually closer to cats than to dogs) will occasionally show up, usually laughing at something. Almost always, they’ll be spotted hyenas, and if not it will probably be a striped one, which will likely be laughing it up just as much despite only spotteds making the laugh-sounding vocalization in real life. Aardwolves and brown hyenas are practically unheard of.
  • Dogs (Canidae) have a few shown. The most common ones are the gray wolf, the domestic dog (a subspecies of the gray wolf: Canis lupus familiaris), and the red fox. Coyotes appear in works set in North America, and dingoes may be used if the work is set in Australia. Once in a while jackals will show up in works set in Africa or India. Foxes besides the red fox are uncommon (the only ones that appear with any regularity being the fennec fox and Arctic fox, with the other 15 or so species almost never being acknowledged except in educational works). The Japanese raccoon dog, locally known as the tanuki, has been iconic in Japanese culture and folklore for centuries, and appears regularly in Japanese media, although more often as its mythologized, shapeshifting form than as the real animal. Dire wolves (now extinct) are sometimes used to make a fantasy series seem more archaic, with one notable example. The name is usually used to refer to some sort of undead wolf though. Even among domestic dogs, only a few breeds show up unless the writers are trying to cram as many breeds in as possible. Most of them are Labs, German Shepherds, Dobermans, English Bulldogs, Beagles, Dachshunds, Poodles (often miniature or toy), Golden Retrievers, Chihuahuas, Great Danes, that sort of thing. When did you ever see a Pharaoh Hound, a Portuguese Water Dog, or a Russkiy Toy in literature or television? If the work is about dog sledding, the dogs tend to be Siberian Huskies regardless of the original work or the preferences of the mushers of the time. The only basenji in all of fiction was the one from Goodbye My Lady.^note Although Spike Milligan's artillery unit briefly adopted one, which they called Havelock, as a battery mascot. Borophagine and hesperocyonine dogs are quietly swept under the table.
  • When we think of bears (Ursidae), we think of the brown or grizzly, the American black bear, the polar bear, and the giant panda (which has been found to genetically actually be a bear^note In case you are wondering, it was long believed giant pandas were actually procyonids, due to their similarity to the red panda. It turns out bears and raccoons had a relatively recent common ancestor, just that pandas are more similar in some ways to that hypothetical ancestor.). Spectacled bears arguably have just one notable representative (Paddington Bear, who came from "Darkest Peru", where the spectacled bear is native) despite being the closest relative to the giant short-faced bears, which, along with the commonly confused cave bear.is common in works set in the Ice Age. Asian black bears (“moon bears”) mainly appear in Asian works, and sun bears and sloth bears are exceedingly rare. Baloo of The Jungle Book fame is almost always depicted as a brown bear rather than the geographically accurate sloth bear, with even the original book calling him a "sleepy old brown bear". Oddly, The Jungle Book (2016) calls him a sloth bear, but he still looks like a brown bear.
  • Lions and tigers and bears, oh my! If they need a large, land-based predator, 90% of the time it will be one of those.
  • Pinnipeds (unranked clade Pinnipedia) are represented by the walrus and a generic seal/sea lion morph. If the heroic characters are penguins, leopard seals will appear as antagonists. Fluffy baby harp seals frequently appear in media for their cute factor, but good luck seeing an adult harp seal.
  • The most common representative of the family Procyonidae is by far the North American common raccoon. Ringtails, kinkajous, olingos, and coatis are uncommon to nonexistent.
  • Red pandas (family Ailuridae, formerly Procyonidae) are somewhat common in the Furry Fandom but are uncommon to rare elsewhere, such that the word "panda" without an adjective will always be assumed to refer to the bear.
  • The best-known species of the family Mephitidae (formerly included in Mustelidae) and the only one likely to appear in a work is the striped skunk. Spotted skunks come in a very distant second (due their appearances in Wild Kratts and generic forest animal toy packs, as well as their known habit of doing handstands). Hog-nosed skunks only appear once or twice in popular culture, and hooded skunks and stink badgers are never featured.
  • Most members of the mustelid family (by far the largest carnivoran family even with the relatively recent exclusion of skunks) aren't seen very often in fiction, but there are a few commonly-used stock species. Smaller "weasels" (subfamily Mustelinae) will be ferrets (not the wild North American black-footed ferret, but rather a domesticated variety of the European polecat) when something cute and playful is called for, or stoats and/or least weasels if a sinister creature is in order. Next in line are the ever-popular otters (typically the sea otter, North American river otter, or Eurasian otter, depending on the setting). Badgers are common in Western European works but not so much elsewhere, and they will look like European badgers even in North America. The ratel (now popularly known as the honey badger) has become more popular as "the most fearless animal". Wolverines appear only occasionally; they are far less well-known than the X-Man bearing their name. Expect most of these to be chattering like raccoons as well. Weasels are sometimes lumped with rodents (which is Older Than Feudalism; the Latin name for such creatures, "Mustelidae", roughly translates to "mice as long as spears"). Chances are the only time you'll see mink in fiction is in the form of fur coats.
• Despite being the closest relatives of the carnivorans, pangolins (order Pholidota) are very rare. Interestingly, pangolins have recently gained a small amount of popularity as an obscure yet endangered animal, especially since articles came out about the pangolin scale trade and more recently speculation that they could be a vector for COVID-19, but they are still not very popular.
• Odd-toes ungulates (order Perissodactyla) include a few familiar species:
  • Horses (by far the best-known odd-toed ungulates) in fiction come in four types: draft horse (usually a Clydesdale), race horse (almost always a Thoroughbred despite many other breeds being used for racing as well), wild/feral horse (mustang), and Generic Critter-You-Sit-On (all others). Domestic donkeys are less common than horses, but still appear quite frequently. Mules appear almost as often as donkeys in North American works, despite needing the latter to create the former. The wild counterparts to domesticated horses and donkeys; the wild asses, the Przewalski's horse, and the extinct tarpan; are shown very infrequently. Zebras are almost always treated as one species and will usually be plains zebras, often wrongly depicted as the size of modern domestic horses. Zebra species and subspecies are seldom identified: educational works occasionally name the Grevy's zebra.
  • Rhinos, often also treated as one species and almost always black rhinos (if not, they'll be white rhinos or Indian rhinos), appear as charging brutes or musclebound thugs in media. Woolly rhinos are prevalent in works about extinct mammals, though the giant hornless rhino Paraceratherium (sometimes referred to by the invalid names of Indricotherium or Baluchitherium) may show up as well due to its status as one of the largest land mammals.
  • Malayan tapirs are fairly common in Japanese media due to their resemblance to the mythical Baku. In the rare instances tapirs are portrayed in Western works, they will also always be Malayan, as the Neotropical species have less distinctive colors.
  • Brontotheres, rhino-like but more closely related to horses, are also quite popular in the subject of prehistoric mammals. Chalicotheres (closely related to rhinos and tapirs) are occasionally mentioned in educational works.
• Even-toed ungulates (order Artiodactyla) include many familiar species.
  • For the family Camelidae, both Bactrian and dromedary camels are common in desert settings. Llamas are quite popular too, especially in works set in the Andes mountains, and alpacas are gaining popularity for their gentle, fluffy appearance, particularly in Japan. Far less likely to appear are the guanaco or the vicuña, the wild camelids that were domesticated to produce the llama and the alpaca respectively.
  • Domestic pigs (family Suidae) are common. Wild pigs will always be warthogs (in Africa) or wild boars (in Eurasia), with others like the red river hog, warty pigs and babirusas almost never being shown. Appearances of peccaries (family Tayassuidae), the pigs' closest cousins and Transatlantic Equivalent, can be counted on one hand (mostly children’s books set in the American Southwest); on the rare occasions they are, they are called by their Spanish name, javelina.
  • Of the two extant species of the family Giraffidae, the giraffe is all but guaranteed to appear when an African savanna is involved. Meanwhile, you can probably count on one hand the number of fictional works in which you've seen an okapi. A related family, Antilocapridae, has just one living species (the pronghorn), which sometimes appears in works set in western North America (and it is usually incorrectly referred to as the "pronghorn antelope" or simply "antelope").
  • Deer (family Cervidae) are represented by red or fallow (in Europe), white-tailed (in North America), sika (in Asia), or generic deer in temperate forest settings, moose in northern North America and sometimes Scandinavia, and caribou/reindeer (which are often confused with more common temperate deer) in the Arctic and in Christmas-themed works. Chital may appear in Indian works. South American deer are rarely if ever acknowledged due to them being overshadowed by more distinctive wildlife.
  • Chevrotains or mouse-deer (family Tragulidae) and musk-deer (family Moschidae) have made virtually zero appearances in fiction.
  • Bovidae is the most diverse family of even-toed ungulates, but this does not necessarily translate to diverse species representation in fiction. There are of course the domestic cattle, sheep, and goats. Works set in western North America feature American bison (usually called buffalo), mountain goats (often conflated with domestic goats) and bighorn sheep (always rams). The European bison, on the other hand, is just as rare in fiction as it is in reality. In the African savanna, expect to see the Thomson's gazelle, the blue wildebeest, and sometimes the African buffalo, an oryx, or a kudu. In South and Southeast Asia, you might see a domestic water buffalo. Japanese serows are semi-common in Japanese media. Nilgai and blackbuck appear in a handful of (mostly older) works set in India. Muskoxen sometimes appear in the Arctic and ibexes in mountains in the Old World, but that's pretty much it. The popular image of the African savanna is so tied to the one in Southern and Eastern Africa (i.e. the former British colonies) that it may come as a shock to learn that gazelles and wildebeest don't exist at all in the remaining stretch of savanna from Senegal to Ethiopia (i.e. the former French colonies). The antelopes that do exist there, like eland, gerenuk, duikers, hartebeest and roan antelope, are much more obscure. And there's a whole host of Asian bovids that are basically invisible in popular culture. Have you seen a chousingha, gaur, kouprey, banteng, anoa, tamaraw, saola, saiga, chiru, bharal, goral, or takin in fiction, much less heard of these animals?
  • The common hippopotamus is extremely common in zoo and African settings. The pygmy hippopotamus, on the other hand, despite being smaller and more docile than its more common cousin and fitting the Huggy, Huggy Hippos stereotype better than the common hippo, is never acknowledged.
  • Of the cetaceans (former order Cetacea, now a suborder of Artiodactyla), we have the generic dolphin (usually a common bottlenose thanks to Flipper), orca/killer whale, humpback whale, sperm whale (used to be the most common depicted whale likely because its oil made it the most valuable to whalers, so this is an association that dropped due to Values Dissonance), and blue whale, pretty much in that order. A character pointing out that killer whales aren't whales is a trope in itself. Never mind that toothed whales (sperm whales, killer whales, bottlenose dolphins) are all more closely related to each other than baleen whales (humpback whales, blue whales); therefore, orcas are both dolphins and whales? "Porpoise" will be treated as a synonym for "dolphin". Narwhals will occasionally appear, and if they do they will always have tusks, even if they're supposed to be female. Don't expect to see too many freshwater dolphins, and chances are, they will be the Amazon's pink river dolphins. Beaked whales, considering their elusive and poorly-known nature, are unsurprisingly not present. Unless you're watching a documentary, don't expect to see the whales' land-based ancestors (Pakicetus and Basilosaurus were traditionally the most common in educational works, but the former has slowly been replaced by the more completely known Ambulocetus, or the "walking whale").
  • Works set in the Ice Age will often feature Megaloceros or "Irish elk" (closer to fallow deer than actual moose or elk). Educational works will sometimes mention entelodonts, but anthracotheres, oreodonts, protoceratids, and fossil giraffids and antilocaprids are rare even there. No further description or species distinctions are to be expected, because herbivores are harmless and therefore boring.
• Meridiungulata, an extinct clade of ungulates endemic to South America including orders Pyrotheria, Astrapotheria, Notoungulata, and Litopterna, are practically never shown in fiction, aside from the horse-like litoptern Macrauchenia, featured on Walking with Beasts, and the hippo-like notoungulate Toxodon, featured on Prehistoric Park .

Miscellaneous

• Hybrid animals tend to be represented exclusively by fictional and usually biologically impossible creations, with the exception of mules and occasionally ligers (the latter of which will usually be treated as a fictional creation anyway). Hybrid plants, despite being far more common than hybrid animals, are never acknowledged as even existing.

Prehistoric Creatures

• Subpages:
  • Stock Dinosaurs (True Dinosaurs)
  • Stock Dinosaurs (Saurischian Dinosaurs)
    • Tyrannosaurus rex
  • Stock Dinosaurs (Ornithischian Dinosaurs)
  • Stock Dinosaurs (Non-Dinosaurs)

Numerous prehistoric creatures of various lineages have gained enough notoriety to appear in stories fairly regularly:

Dinosaurs

Saurischia & Ornithischia

• Likely have the widest variety in fiction. Before Jurassic Park, however, works were unlikely to show anything beyond sauropods, Stegosaurus, Allosaurus, Iguanodon, Tyrannosaurus rex, ceratopsians, ankylosaurs, and hadrosaurs. And then that movie added Velociraptor (or rather an oversized generic dromaeosaurid with the name Velociraptor slapped on it) to the stock roster. They almost never get properly depicted with feathers. The third Jurassic Park movie made Spinosaurus popular (it was indeed longer than Tyrannosaurus), but the fact that it was really a weak-jawed aquatic piscivore that could not, and did not have to, compete with the large terrestrial theropods is likely to be ignored (More recent discoveries have shown Spinosaurus to be even more aquatic, with short hind legs and a paddle-like tail, but, as always, popular culture is slow to adjust). If you get more specific, the taxonomy pools become smaller:
  • Basal saurischians (order Saurischia) are limited to Herrerasaurus and Eoraptor.
  • Large theropods (order Saurischia, suborder Theropoda) are usually T. rex, Allosaurus, Spinosaurus, or sometimes Dilophosaurus. Less, commonly, Ceratosaurus, Megalosaurus, Albertosaurus, Gorgosaurus, Tarbosaurus, Giganotosaurus, Carcharodontosaurus, Baryonyx, Suchomimus, or Carnotaurus will appear. Yutyrannus has been recently gaining some popularity due to being the largest known dinosaur to have preserved direct evidence of feathers. Birdlike theropods are mostly represented by dromaeosaurs (namely Deinonychus or Velociraptor, though Dromaeosaurus, Utahraptor, and Microraptor show up occasionally), Archaeopteryx, and ornithomimids (Ornithomimus, Struthiomimus, or Gallimimus, with Dromiceiomimus [possibly synonymous with Ornithomimus] occasionally appearing in older works). Oviraptor and Stenonychosaurus (a name that generally appears in older works, as until quite recently, it had been classified as Troodon, the name which it is still commonly referred to now, but once again, Science Marches On). Therizinosaurus is getting popular due to its Wolverine Claws as well being a theropod that's herbivorous as opposed to carnivorous, though it's still not quite common in media. Non-birdlike small theropods are uncommon. Coelophysis and Compsognathus, if you're lucky (you might see Ornitholestes in older works and Sinosauropteryx in newer works, but don't hold your breath).
  • Sauropods (order Saurischia, suborder Sauropodomorpha) are represented by Brontosaurus, Apatosaurus, Diplodocus, and Brachiosaurus. Camarasaurus, Saltasaurus, Amargasaurus, Barosaurus, Mamenchisaurus, Argentinosaurus, Alamosaurus, and Supersaurus if you're lucky. "Prosauropods" will always be Plateosaurus, and even that's pushing it (although Dino of The Flintstones fame loosely resembles this group).
  • The only basal ornithischians (order Ornithischia) you might see are Lesothosaurus and Heterodontosaurus, but even those are rare.
  • The only stegosaur (order Ornithischia, suborder Stegosauria) is Stegosaurus (although Kentrosaurus is semi-common in edutainment works).
  • The only ankylosaur (order Ornithischia, suborder Ankylosauria) that frequently appears is Ankylosaurus, although older works will sometimes use Euoplocephalus or Scolosaurus^note formely synonymous with Euoplocephalus until 2013 instead (the anatomy of Ankylosaurus itself was poorly known until 2004). Nodosaurids, which are practically unheard of outside of educational works, will usually be Nodosaurus, Edmontonia, Polacanthus, Sauropelta, or Gastonia.
  • There are two main ceratopsids (order Ornithischia, suborder Ceratopsia): Triceratops and Styracosaurus (although older works will sometimes use Centrosaurus). More rarely, Torosaurus, Chasmosaurus, and Pachyrhinosaurus may show up. More basal ceratopsians are rarely heard of (Protoceratops and Psittacosaurus, and only in edutainment works).
  • Pachycephalosaurs (order Ornithischia, suborder Pachycephalosauria) aren't quite as commonly seen as their ceratopsian cousins; they will basically always be Pachycephalosaurus and use their head to smash everyone they see. Stegoceras occasionally pops up in older works.
  • Hadrosaurs (order Ornithischia, suborder Ornithopoda) are usually represented by Parasaurolophus or Edmontosaurus/Anatosaurus (whatever name it's referred to as), and neither is likely to be named (Corythosaurus and Lambeosaurus used to be somewhat common, and Maiasaura will occasionally appear in modern works). Non-hadrosaur ornithopods are pretty much only represented by Iguanodon (you might see Camptosaurus, Dryosaurus, Hypsilophodon, Muttaburrasaurus, Ouranosaurus, and Orodromeus if you're really lucky). The only exception is Tenontosaurus, which frequently appears in educational works as the prey of Deinonychus.

Saurischian dinosaurs

Theropods

1. Tyrannosaurus rex, the most famous and, supposedly, the most powerful dino of the bunch. Had huge jaws but tiny front claws with only two fingers, a juvenile specimen of T. rex has been found with avian scales which are a stunted type of feather. Far less-common smaller relatives of the rex in media are Tarbosaurus found in Asia (often believed the "twin" of Tyrannosaurus, and at one point classified as another species within the Tyrannosaurus genus), and Gorgosaurus, Albertosaurus and Daspletosaurus, all from Late Cretaceous North America, like the rex (albeit slightly earlier). From even further north comes the Nanuqsaurus ("polar bear lizard"), a smaller tyrannosaurid that is usually depicted with a coat of white, fluffy feathers to keep it warm. There's no direct evidence that Nanuqsaurus had feathers, but the more primitive Asian tyrannosaur relative Yutyrannus definitely did, so it's a reasonable speculation.
2. "Raptors", usually called Velociraptor and popularized by the dromaeosaurids in Jurassic Park, which are closer in size to Utahraptor but are actually meant to be Deinonychus. ^note The palaeontological advisor of the original novel, Dr. Jack Horner, considered Deinonychus to actually be a species within the Velociraptor genus at the time... even though they lived on opposite ends of the globe about 40 million years apart from one another. Note that "raptor" traditionally means a bird of prey, such as an eagle or a hawk — and it ultimately comes to us from the Latin word for "to seize", rapere. Of course, it turns out that all birds are raptors, descended from maniraptors very closely related to Velociraptor, Deinonychus, or Utahraptor, so this usage is accidentally correct in a way. Raptors are the first examples that today come to most people's minds of dinosaurs that are considered fast and intelligent, instead of slow and lumbering, as most dinosaurs were thought to be prior to the formal description of Deinonychus in 1964, by John Ostrom. Deinonychus lived in Early Cretaceous Montana and was about nine feet long, Utahraptor lived in Early Cretaceous Utah (although it's a bit older than Deinonychus) and was twice its length, and proper Velociraptor lived in Late Cretaceous Asia (the best-known species within the genus is tellingly named Velociraptor mongoliensis) and was six feet long. The namesake Dromaeosaurus was the same size as Velociraptor and lived in Late Cretaceous Alberta.
3. Troodonts like Stenonychosaurus (historically lumped into the now dubious genus Troodon) or Saurornithoides were similar to dromeosaurs, and are usually lumped into the "raptor" ensemble despite being a distinct family of theropods, with weaker sickle-feet and generally slighter builds (although they are closely related). Stenonychosaurus was once claimed the "smartest dinosaur", and is the origin of the curious Dinosauroid hypothesis, made in The '80s.
4. Allosaurus, the other large carnivorous dinosaur prominent along with Tyrannosaurus. Distinguished from T. rex by having three fingers, larger arms, brow horns, a shorter skull, and a smaller build. Standard-issue for any depiction where a Jurassic rather than Cretaceous predator is required. Other less-common choices of Jurassic big theropods are the 18 ft long horned Ceratosaurus (living alongside the Allosaurus, and possibly the hyena to its lion in life), and the 24 ft long Megalosaurus from Middle Jurassic Britain — the first dinosaur named by science (hence its rather generic title, meaning "big lizard"), in 1824 England, with an extremely complex Science Marches On story.
5. Giganotosaurus, Carcharodontosaurus and Acrocanthosaurus, larger and younger relatives of Allosaurus, all from the Early to Middle Cretaceous (Giganotosaurus and Carcharodontosaurus from the latter in Argentina and North Africa respectively, Acrocanthosaurus the former in North America). Giganotosaurus, at least — and possibly also Carcharodontosaurus — is believed to have been even bigger than T. rex, though there does not seem to be quite as much of a pop cultural rivalry there as there is between the rex and Spinosaurus (see below).
6. Carnotaurus and its lesser-known cousin Majungasaurus, which looked like smaller, horned tyrannosaurids, but were actually part of another branch, the Abelisaurs. The two-horned, short-faced Carnotaurus of Late Cretaceous Argentina has left excellent prints of skin with tubercles. Its arms were, if anything, even more useless than those of T. rex. The one-horned Majungasaurus was found in Late Cretaceous Madagascar. Together with Coelophysis (see below) and T. rex itself, Majungasaurus is one of the few dinosaurs which have been believed (at one point) to have occasionally eaten its own kind.
7. Spinosaurus, a North African Middle Cretaceous dinosaur found in the Sahara regions, which became famous in 2001 due to its starring role in Jurassic Park III. it had distinctive dorsal spiny crest and crocodile-like jaws, and today is considered the largest of all the carnivorous dinosaurs, even bigger than the classic record-holder T. rex, and often shown in a fight against it. The fact that the spinosaurs mostly ate fish and had an aquatic lifestyle is quite unlikely to be discussed outside of educational works (or from the pro-Tyrannosaurus contingent speculating on how such a fight would go). Recently found to be a croc-like swimmer with stubby hindlegs and a large tadpole-like tail, in 2020, making incorrect all its more classic depictions of the classic bipedal carnivorous dinosaur.
8. Smaller spinosaurids include the Baryonyx — a more normal-looking Early Cretaceous carnivore found in England in The '80s and noted for its numerous teeth in its crocodile-like jaws, and huge thumb-claws probably used for fishing — and Suchomimus — another African dinosaur, not quite as big as Spinosaurus itself and lacking the huge sail, but otherwise fairly similiar in appearance. Less likely to appear in pop culture are the even smaller Icthyovenator and the humourously-named Irritator, of Early Cretaceous Southeast Asia and South America, respectively, and the gigantic Brazilian Oxalaia, which was almost as big as Spinosaurus itself and seems to have very much resembled it, sail and all (to the point where some scientists believe them to be the same animal).
9. Dilophosaurus, another dinosaur made famous due to the Jurassic Park franchise, in particular the first book and movie. Living in North America around 190 million years ago (so Early Jurassic), it was one of the first large theropods that ever appeared. It was named for the distinct pair of parallel crests on its head, and was about 18 feet long, weighting around 500 kgs. It will often be inaccurately depicted as more human-sized, spitting venom and resembling a frilled-necked lizard, thanks to Spielberg and Crichton. It was long thought to have an extremely weak and fragile jaw, but a reanalysis conducted in 2021 determined that this was incorrect and that the animal actually had a much more robust skull and a bite capable of breaking bone, which along with a lung structure similar to modern birds giving it a high metabolic rate meant that it was an energetic, apex predator.
10. Ornithomimids or "ostrich-mimic dinosaurs", slender running bipeds of small or medium size, specifically the smallish Ornithomimus, Struthiomimus and Dromiceiomimus of Late Cretaceous North America and the bigger Gallimimus of Late Cretaceous Asia. Often cited as examples of harmless or peaceful dinosaurs because of their absence of teeth. Their speed and agility will often be emphasized.
11. Oviraptorids (usually called Oviraptor, but often modelled after its close relative Citipati, both found in Late Cretaceous Mongolia) can be mixed up with the ornithomimids, being similar in look but with shorter bills, more developed feathers, and often a cranial crest. Both ornithomimes and oviraptors tend to be depicted as nest-robbers, preying on other dinosaurs' eggs, a bit like raccoons or foxes robbing chicken eggs from a farm. However, its more likely in real life that both groups were omnivorous, with certain species having more herbivorous tendencies, not unlike ground-dwelling birds today.
12. Compsognathus or "Compy" from Europe, which is famous for being one of the smallest dinosaurs, often stated to be "chicken-sized" and "chicken-looking". Often incorrectly said to be the smallest of them all and depicted with two-fingered, T. rex-like hands (it actually had three fingers per hand). Ornitholestes and Coelurus were similar but a bit bigger, both from North America. Guanlong, found in 2006, was one of the first tyrannosaur ancestors, and its suffix "long" ("dragon" in Chinese) betrays the place it was found. All of these small carnivores lived in the Late Jurassic.
13. Archaeopteryx, another dinosaur from Late Jurassic Europe, was actually smaller than Compsognathus, and is the iconic link between non-avian dinosaurs and birds. Popularly called the "first bird", though in reality it's a bit more complicated than that. Recently becoming popular is also the Early Cretaceous Microraptor found in the year 2000 in China, distinctive for its "four-winged" look and tiny size, also being smaller than Compsognathus. Feathers among dinosaurs seem to have been fairly widespread, at least among the theropods: from the small oviraptorosaur Avimimus found in Mongolia in 1981 with its arm-bones that show attachment points for feathers, to the small "Liaoning theropods" found in China since 1997, to even the large tyrannosaur relative Yutyrannus, found in 2011 (also in China, see above).
14. Therizinosaurus, a big theropod whose Wolverine Claws have made it famous. This alongside the fact it was a herbivore and that it is known to have been covered in feathers are the biggest reasons it's considered to be one of the strangest looking dinosaurs ever, together with other two equally big birdlike theropods, the giant swamp-dwelling ornithomimosaur Deinocheirus (originally found in 1965, but was only known from two giant arms until more complete fossils were found in 2013) and the giant oviraptorosaur Gigantoraptor found in 2009. Another Vegetarian Carnivore theropod related to the therizinosaur was the smaller, 7-meter long Segnosaurus. Initially, both Therizinosaurus and Deinocheirus were thought to be huge meat-eaters because of the original incompleteness of their remains, but they're now understood to have been herbivores, and not quite as big as previously thought. All these four dinosaurs were found in Mongolia, with Therizinosaurus and Deinocheirus being contemporaneous in the Late Cretaceous and Segnosaurus and Gigantoraptor coming from the Middle Cretaceous.
15. Coelophysis, one of the first true dinosaurs, a small (9 ft long and 30 kg) and skinny predatory North American theropod, with a long neck, slender skull, and agile legs, and one of the most common small-sized dinosaurs in the fossil record. This is one the only dinosaurs from the Late Triassic period that you're likely to see. The Coelophysis is sometimes believed to have eaten its own kind ^note The scientific consensus has gone back and forth on this point, as detailed by Hank Green in this video . A bigger and less ancient Coelophysis relative is the aforementioned Dilophosaurus. Rarer in media are Eoraptor, Staurikosaurus and Herrerasaurus, Late Triassic bipeds of South America, long believed the "first dinosaurs" and the ancestors of all the other dinos since their discovery.

Birds

1. Terror birds (phorusrhacids such as Phorusrhacos), who — being birds — are true dinosaurs, but are generally grouped with Cenozoic mammals due to living at the same time. They are usually treated as essentially the raptors of the Age of Mammals, being the apex predators of South America for much of the Cenozoic before finally going extinct a mere 2 million years ago. Argentavis was a giant condor also from Cenozoic South America, with a 20 foot wingspan, like many giant pterosaurs, and weighing as much as an adult human. It is considered one of the largest birds ever, and hands-down (talons down?) the largest flying bird ever.
2. Gastornis (formerly known as Diatryma) is sometimes lumped in with phorusrhacids due to its similar outward appearance, despite having belonged to a very separate group of birds and lived tens of millions of years before them in North America and Europe during the Eocene. Gastornis / Diatryma was classically shown as the great predator of early Cenozoic, eating mammals like the fox-sized ur-horse Eohippus, but is now understood to be one of the Cenozoic's first megaherbivores, using its huge beak (which noticeably lacked a hooked tip, a key trait of all predatory birds) to crush fruits and nuts.
3. Raphus cucullatus (aka the Dodo), a flightless relative of pigeons that was endemic to the island of Mauritius (east of Madagascar). It's among the most famous, popular and iconic extinct animals alongside the dinosaurs and Ice Age megafauna. Other known historically-extinct animals are the Eurasian Aurochs (Bos primigenius, the wild ancestor of cattle); the South African Quagga (Equus quagga), a zebra relative with incomplete stripes; the European Tarpan Horse (Equus ferus, one of the ancestors of domestic horses); the northern oceanic Great Auk (Pinguinus impennis, the bird originally called "penguin" because of its external look very similar to a modernly-intended penguin); the Madagascan Aepyornis, or Elephant Bird (which laid the biggest known eggs of a land animal ever, and is believed to have been the biggest bird of all time, although its closest living relative is the tiny kiwi); the Giant Moa or Dinornis (another flightless bird with almost absent wings, living in New Zealand, perhaps the tallest bird ever, but surprisingly not quite as closely related to the kiwi as the elephant bird was); the Haast's Eagle (Hieraaetus moorei), a large bird of prey that lived in New Zealand and hunted moas; the Steller's Sea Cow (Hydrodamalis gigas, a giant relative of the manatee of the northern Pacific, the size of an adult elephant or a big orca); the Passenger Pigeon (Ectopistes migratorius, perhaps the least exotic-looking, similar to a house pigeon in size and shape, but once found across North America in the trillions). Unlike truly prehistoric animals, all them went extinct in historical times — during the 17th century in the case of the dodo. Instead of natural disasters or cataclysmic events, their demise was caused by us humans. Due to this, they are often used as a symbol of humankind's own ability to drive entire species to extinction, especially the dodo (think "as dead as a dodo"). The aurochs is frequently cited in ancient/medieval European literature as a big wild game and as a symbol of power.

Sauropods

1. Sauropods or "long-necked dinosaurs", most prominently the North American Brachiosaurus (more correctly, the African Giraffatitan^note Most of the fossils that had previously been classified as Brachiosaurus actually belonged to the more recently-identified Giraffatitan, which was formerly considered a species of Brachiosaurus. What we have left that is still considered Brachiosaurus paints a very unclear picture of what it actually looked like, so when you picture Brachiosaurus you're actually picturing Giraffatitan), notable for its upright giraffy shape and huge size; the slenderer North American Diplodocus, famous for its extreme length and immensely long tail; and the North American Brontosaurus and Apatosaurus, which were both shorter but more massive than the related Diplodocus. For more than a century, Brontosaurus was considered a junior synonym for Apatosaurus, but a 2015 study proposed that several species (including the type species, Brontosaurus excelsus, named way back in 1879) are different enough from Apatosaurus to warrant a separate genus name. Diplodocus, Brontosaurus, and Apatosaurus had "whips" at the end of their long tails, while the brachiosaurs were much shorter-tailed.
2. More sauropods include the shorter-necked Late Jurassic North American Camarasaurus, the Middle Jurassic European Cetiosaurus, the armored South American Saltasaurus of the Late Cretaceous, the especially long-necked Late Jurassic North American Barosaurus, the even more long-necked Late Jurassic Chinese Mamenchisaurus, and the top contenders for biggest land animal of all time, among them the Late Cretaceous Dreadnoughtus and the earlier Argentinosaurus (both of which were found in Argentina). Once, sauropods as a group were believed to be semi-aquatic creatures that had to live in swamps because they were too heavy to stand on land. Today we know they were not only terrestrial, but even able to rear up on the two hind legs alone, like modern elephants. Some paleontologists argue that the contemporary view of purely terrestrial sauropods may be an over-correction, and that some of species may have been perfectly comfortable in a more wetland environment, such as the smaller Nigersaurus of Early Cretaceous North Africa, whose wide mouth and comb-shaped teeth might have been adaptations for straining through water plants and even small invertebrates, similar to the feeding habits of today's flamingos. Another classic error is to depict sauropods as having elephant-like nailed feet, where in reality they were clawed. Sauropods lived around the entire world, and while the most famous of them lived during the Jurassic, the sauropods survived well into the Cretaceous period (as noted above, the very biggest of them were Cretaceous dinosaurs) and may have been among the very last dinosaurs at the end of the Mesozoic.
3. Plateosaurus, one of the first true dinosaurs, a bulky (24 feet long and about two tons in weight) herbivorous precursor of the even larger sauropods, and the most common dinosaur found in Europe. Along with Coelophysis, it is one of the only two Late Triassic dinosaurs likely to appear in a work. Once thought to be carnivorous, or quadrupedal like a true sauropod, but is now thought to have been a bipedal herbivore. Plateosaurus is the most famous of the "prosauropods", a group including the Early Jurassic North American Anchisaurus, the Late Triassic European Thecodontosaurus, Early Jurassic African Massospondylus and Late Triassic South American Mussaurus and Riojasaurus, among others. Anchisaurus was the first dinosaur found in the USA (as early as 1818!), Thecodontosaurus was one of the first found in Europe (in England). Massospondylus is best known for an abundance of nests and eggs found in the 2000s, while Mussaurus was only known from eggs and hatchlings, until 2013. Riojasaurus was sauropod-like and bigger than Plateosaurus.

Ornithischian dinosaurs

Thyreophora

1. Stegosaurus, familiar thanks to its famous back-plates, tail spikes, and brain no bigger than that of a cat's despite the fact that it's as big as a bus. This contributed to the idea that dinosaurs in general were unintelligent and went extinct due to this failing. It's unknown how much intelligent Stegosaurus was in Real Life. It was a Late Jurassic North American dinosaur, and is usually depicted as the nemesis of Allosaurus, equivalent to the Cretaceous T. rex vs. Triceratops pairing. Sometimes Stegosaurus is shown with an incorrect placement of the plates and/or tail spikes. The African Kentrosaurus and the Chinese Tuojiangosaurus and Chungkingosaurus were fellow stegosaurians that lived around the same time, but were smaller and spikier. The exact role of their plates is still controversial among scientists. A later animal called Dravidosaurus, found in India, was believed to have shown stegosaur survival well into the end of the Cretaceous, but it had been identified as a non-dinosaurian sea reptile in 1991, leading to the belief that the stegosaurs have gone extinct during the Early Cretaceous before the end of the Dinosaur Age, until it was re-established as a stegosaur again in 2017.
2. Ankylosaurus, a large quadrupedal herbivore distantly related to Stegosaurus, famous for its heavy dorsal spiny armor, short legs, wide body, armored head, and rounded clubbed tail. Often pictured incorrectly in media, with armor more similar to the other ankylosaurian dinosaurs. Lived alongside with Tyrannosaurus and is often portrayed fighting it. Despite its heavy armour, its underbelly was soft and unprotected.
3. Euoplocephalus, Nodosaurus, Polacanthus, Pinacosaurus, Scelidosaurus, Minmi, and others were ankylosaurians all smaller and earlier than Ankylosaurus (not all of them having the club tail), and can be used occasionally as substitutes of it in media. Ankylosaurians lived for most of the Mesozoic Era and have been found around the world (including Australia and even Antarctica, which was still ice-free at the time), with Scelidosaurus being the earliest known (Early Jurassic Europe). Hylaeosaurus of Early Cretaceous England is one of the three animals originally named dinosaurs by English paleontologist Richard Owen, together with Megalosaurus (above) and Iguanodon (below). All the three are visible as outdated life-sized sculptures in the Crystal Palace Park in London.

Marginocephalia

1. Triceratops, popularly called the "three-horned dinosaur" or "Trike" is the best-known Ceratopsian, and one of the best-known dinosaurs. Often, and as far as we know, accurately, depicted in a predator-prey relationship with the T. rex. Such a fight would truly be the Behemoth Battle we see in the all the illustrations, as the Triceratops would have had a devastating charge, and is often likened — with reason — to a rhinoceros or bull. It's been speculated that the Triceratops may have used its distinctive frill and horns to attract potential mates, and while there's no way to be sure (we're not even sure they lived in herds), the image of males grappling with their horns to impress females is a common one in dinosaur-related media. Almost all of the big ceratopsians lived in North America during the Late Cretaceous, but only a few, among them Triceratops, were hit directly by the Rock Falls Everyone Dies event. Some recent evidence suggests that it — and, by extension, the other ceratopsians — might possibly have also possessed small quill/bristle-like feathers on their backs, although this has yet to make its way into pop cultural portrayals.
2. Styracosaurus, smaller (around half the size) and a bit earlier than Triceratops, but known for its spiky frill that slightly resembles the head of the Statue of Liberty, and other ceratopsids like the triangle-frilled Chasmosaurus, the huge-headed Torosaurus and Pentaceratops, the one-horned Centrosaurus, and the thick-nosed Pachyrhinosaurus, which can be used as substitutes for Triceratops. Centrosaurus had strange "hooks" on its frill and has left huge fossil herds drowned in ancient floods. "Monoclonius" was perhaps a juvenile Centrosaurus; Torosaurus has been argued by some to be a particularly old Triceratops. Pentaceratops means "five horned face" but actually only had three (the other two are actually its massive cheekbones). All of these dinosaurs lived in Late Cretaceous North America, although with the exception of Torosaurus and possibly Pachyrhinosaurus, they all lived a bit earlier than Triceratops.
3. Protoceratops, nicknamed the "sheep of the Cretaceous" for its abundance in the Late Cretaceous Mongolian fossil record, is usually depicted in the same roles as Triceratops as well, only much smaller and without horns which makes it appear "cuter". Just as T. rex and Triceratops are often shown as rivals, Velociraptor is frequently depicted as Protoceratops's archenemy, thanks to a well-preserved fossil of the two in combat. One of the most famous Asian dinosaurs, the Protoceratops has left abundant fossils including nests and hatchlings, and was once believed the owner of the first dino eggs ever found (it later turned out those were actually Oviraptor eggs), and sometimes (like the other ceratopsians) is thought to have been slightly omnivorous instead of entirely herbivorous (not unlike modern pigs). Also sometimes thought to have inspired the mythical griffin, with its quadrupedal body and superficially birdlike head — its fossilized remains, still common today, would have been well-known to ancient peoples across Central and Western Asia, where the myth originated.
4. Pachycephalosaurus, smaller two-legged herbivores famous for having extremely thick skulls which they may have used to headbutt each other, kind of like bighorn sheep. Also famous for the tubercles and hornlets around their skulls. Sometimes incorrectly portrayed as carnivores, though they could have been somewhat omnivorous, not unlike what has been proposed with their closest relatives, the ceratopsians. Contrasting with hadrosaurs, Pachycephalosaurs are among the rarest dinosaurs in fossil record, all from Late Cretaceous Asia and North America: the "biggest" is the namesake Pachycephalosaurus (not larger than a cow), and the most complete in fossils is the man-sized Stegoceras, both from North America.
   • The spiky-headed Dracorex hogwartsia is also notable as one of the few dinosaurs named for a pop culture reference, although the genus is now considered a juvenile form of Pachycephalosaurus. The validity of the Stygimoloch genus name on the other hand is something that is still debated, stratigraphic evidence shows Pachycephalosaurus mostly being found on lower layers and Stygimoloch mostly found from upper layers, and unpublished specimens of adult sized Stygimoloch point towards the possibility that Stygimoloch is a distinct species from Pachycephalosaurus.^note  However since the Pachycephalosaurus genus was named first its name takes priority over the Stygimoloch genus name, which would result in the name changing from S.spinifer to P. spinifer.
5. Psittacosaurus, Microceratus and Leptoceratops were early ceratopsians. The first two were from Early and Middle Cretaceous Asia respectively, the third from Late Cretaceous North America. the Psittacosaurus is named the "parrot dinosaur" for the shape of its skull and uncinated beak, and was once believed the ancestor of all the other ceratopsians (with the discovery of even older and more primitive ancestral ceratopsians from Late Jurassic China such as Yinlong and Chaoyangsaurus, we now know it wasn't). Since the 2000s, Psittacosaurus has revealed exceptional remains, among them prints of skin with horny quills on its tail. Microceratus was one of the smallest non-bird dinosaurs (2 ft long) and was once called Microceratops or Graciliceratops; Leptoceratops was as large as Psittacosaurus and lived alongside Triceratops and Tyrannosaurus.

Ornithopoda

1. Hadrosaurs or "duck-billed dinosaurs" (usually either Edmontosaurus or Parasaurolophus, more occasionally Corythosaurus or Lambeosaurus and others like Saurolophus or Kritosaurus), large herbivorous dinosaurs which could shift from bipedal to quadrupedal. Their head-crests varied a lot, the most famed being the long prominence of Parasaurolophus. The most popular hadrosaurs were Late Cretaceous North American. Edmontosaurus was particularly ducklike with its flat bill and has left an amazing 10,000 individuals including petrified mummies, Corythosaurus had a big round crest like a cassowary bird, Lambeosaurus had a complex crest and was once believed the biggest hadrosaur, Saurolophus had a small "horn" and was also found in Asia (indicating these two continents were once connected), Kritosaurus had (allegedly) a bump on its nose and was (allegedly) found also in South America (though these more likely belong to a related dinosaur). The namesake Hadrosaurus was the first United States dinosaur recognized as such, in 1858, from a partial skeleton that showed for the first time big dinosaurs were bipedal (see Prehistoric Life - Dinosaurs). Among exclusively Asian hadrosaurs there are the "unicorn" Tsintaosaurus (although more recent reconstructions show its horn as less unicorn-like) and the gigantic Shantungosaurus.
2. Hadrosaurs are often thought to be noisy animals, as their crests were mostly hollow and would have been ideal for bellowing, trumpet-like calls, which would have been useful in warning of predators, coordinating migration, mating calls, and the like, as evidence suggests that most of the hadrosaurs lived in large herds. In 1997, researchers from Sandia National Laboratories and the New Mexico Museum of Natural History (both in New Mexico, USA) collaborated to recreate the crest cavity of a Parasaurolophus using early 3-D printing technology, giving us some idea of what it might have sounded like (samples can be found on Youtube with ease). The hadrosaurs — particularly Edmontosaurus — were once believed semi-aquatic, with webbed hands like a literal duck, and it was once thought that the distinctive crests were used for snorkeling. Though most of this has since been thrown out, the hadrosaurs probably were at least somewhat comfortable in and around water, as a lot of their habitat — particularly the famous Dinosaur Park Formation in Canada, where iconic species like Lambeosaurus, Corythosaurus, and Parasaurolophus have been found — was low-lying swampland at the time. Maiasaura is famous among hadrosaurs and dinosaurs in general as "the caring dinosaur" thanks to its fossil nesting sites found in Montana in The '80s, the first undoubtable evidence of parenting behaviour among dinosaurs, striking a resounding blow against the perception of dinosaurs as mindless eating machines.
3. Iguanodon, one of the first non-avian dinosaurs discovered, similar to a hadrosaur but without the "duckbill", and known for its thumb spikes and for its well-preserved remains found in Europe, making it perhaps the most famed European dinosaur. Also known for a famous case of Science Marches On, as earlier reconstructions showed the thumb spike as a rhinoceros-like nose horn, and the famous Crystal Palace dinosaur statues still show that outdated image of the animal, Iguanodon is also famously known as a British dinosaur but all British species of the genus are no longer valid. Both hadrosaurs and iguanodonts are often believed very social animals. Both were Cretaceous animals, but Iguanodon lived before hadrosaurs in the Early Cretaceous and was possibly one of their ancestors. The smaller Camptosaurus was earlier, from Late Jurassic North America, and likely prey for Allosaurus. The long-tailed Early Cretaceous North American Tenontosaurus, also smaller than Iguanodon, is classically depicted as a fodder for the "raptor" dinosaur Deinonychus due to fossil findings, although this idea has been challenged. There's also the more hadrosaur-like Ouranosaurus, which had a sail on its back and a flat bill, and lived in what is now the Sahara Desert but was mostly swampy floodplains at the time. The bulge-nosed Muttaburrasaurus is one of the few known dinosaurs from Australia. Both Ouranosaurus and Muttaburrasaurus lived in Early Cretaceous and were smaller than Iguanodon.
4. Small bipedal swift-running herbivores like Hypsilophodon, Dryosaurus, Thescelosaurus, Orodromeus, Leaellynasaura, Scutellosaurus, Heterodontosaurus, Lesothosaurus, and Nanosaurus could appear in dinosaur media as generic background ambiance or prey animals, though often they don't play a huge role and aren't even named. Such animals lived throughout the whole Dinosaur Age in Real Life. Hypsilophodon, named the "gazelle dinosaur", was once believed to have been an arboreal animal like a green iguana, and lived alongside Iguanodon in Early Cretaceous Europe; Heterodontosaurus had four tusks like a baboon or a peccary and was from Early Jurassic Africa; Lesothosaurus was contemporary to the latter but with a more generic appearance; Scutellosaurus had a light armor and was possibly prey for Dilophosaurus in Early Jurassic North America. Leaellynasaura lived in Early Cretaceous Australia, Thescelosaurus and Orodromeus were neighbors to Tyrannosaurus and Triceratops/their relatives in Late Cretaceous North America, and Nanosaurus (formerly known as Othnielia or Othnieliosaurus) and Dryosaurus coexisted alongside Stegosaurus, Allosaurus, and many iconic sauropods in Late Jurassic North America. While Scutellosaurus is believed to be an early ancestor of Stegosaurus and Ankylosaurus, the others are traditionally classified as small ornithopods (although this has been called into question).

Non-dinosaur reptiles

Pterosaurs

1. Pterosaurs (order Pterosauria) will usually be either Pteranodon, Rhamphorhynchus, or a completely fictional blend of the two; more occasionally, Quetzalcoatlus, Pterodactylus, or Dimorphodon might also appear. Other species are exceedingly rare; the group as a whole is often erroneously called "flying dinosaurs" despite being cousins to Dinosauria. In earlier educational works, the order would be split into the long-tailed "rhamphorhynchoids" and the short-tailed "pterodactyloids", but the former is now an obsolete term, and the group Pterodactyloidea is distinguished from other pterosaurs by traits that are more precise and technical. Once, like dinosaurs, pterosaurs were depicted as cold-blooded scaly animals, often with improbable traits like eagle-like claws or bat-like wings. Most scientists once thought they were bad fliers or simple gliders, but even earlier fiction tended to show them as mighty fliers. They will also frequently be called "pterodactyls", which in science is a term restricted only for members of the suborder Pterodactyloidea, described below.
2. The most iconic large pterosaurs are all from the Pterodactyloidea group. They all had stubby tails, but some had head-crests and/or teeth, and others were devoid of them. Some were huge, others tiny, and lived from Jurassic to the end of the Cretaceous. Of these, the head-crested Pteranodon of Late Cretaceous North America, with a 20-foot wingspan, is the go-to pterodactyl in popular media, often portrayed as oversized, fanged, and carrying off cave-people or small dinosaurs with its inaccurately bird-like talons; it is now thought to be a seagoing albatross analogue that may have dived for fish like a gannet. The North American Quetzalcoatlus, with its 40-foot wingspan, is classically cited as the biggest pterosaur, at least after its finding in the seventies, claiming a title previously held by Pteranodon. Quetzalcoatlus lived at the very end of the Mesozoic alongside T. rex and Triceratops and takes its name from the Feathered Serpent god of Aztec Mythology; it is today thought to have actually spent much of its time on the ground, like a huge stork. Other pterodactyloids that may appear in educational works are Hatzegopteryx of Late Cretaceous Romania (an even bigger relative of Quetzalcoatlus that hunted dwarf dinosaurs), Tropeognathus (a genus from Early Cretaceous South America known for the round crests on the end of its beak and being the largest pterosaur known from the Southern Hemisphere; this one famously appeared in Walking with Dinosaurs, albeit misnamed as the related Ornithocheirus and oversized for dramatic effect), Pterodaustro, (also from Early Cretaceous South America, with bizarre baleen-like teeth used for filtering plankton like a flamingo), and Dsungaripterus of Early Cretaceous Asia (a specialized shellfish hunter with blunt teeth at the back of a toothless beak). Ironically, Pterodactylus itself, from Late Jurassic Europe, is quite rare to see in fiction, despite rubbing shoulders with the premiere bird ancestor in pop culture, Archaeopteryx.
3. The other traditional suborder is "Rhamphorhynchoidea", named after the gull-sized, fin-tailed Rhamphorhynchus of Late Jurassic Europe (which is as famous if not more so as its short-tailed contemporary, Pterodactylus). However, this suborder is paraphyletic, unlike the Pterodactyloidea, which arose from within the Rhamphorhynchoidea as opposed to a more distant common ancestor. Early pterosaurs flourished throughout the Jurassic and Triassic, and while they never got as large as the true pterodactyls, they were notable for their often big teeth and long tails, but some evolved shorter tails independently of pterodactyloids. Some other primitive pterosaurs that have made notable appearances in pop culture or documentaries include the big-headed Dimorphodon of Early Jurassic Europe (which was a pterosaurian staple in older palaeo-art, but faded out of the public consciousness until its grand return in Jurassic World), the diminutive, big-eyed, and nocturnal Anurognathus (which was portrayed as a sort of Jurassic oxpecker in Walking with Dinosaurs and as an aerial swarming menace in Primeval), Eudimorphodon of Late Triassic Europe (one of the oldest pterosaurs known), and the Late Jurassic Asian rhamphorhynchoid Sordes, known for having left the first tracks of furry skin among pterosaurs, found in the seventies.

Marine Reptiles

1. Jurassic World has the only notable appearance of a mosasaur in fiction (although they are common in paleo-documentaries). Aigialosaurs and Dolichosaurs, on the other hand, are entirely nonexistent.
2. Sea-dwelling reptiles, most commonly the long-necked plesiosaurs such as the 40-foot long Elasmosaurus of Late Cretaceous North America and the much smaller (10 feet long) Plesiosaurus of Early Jurassic Europe. In fiction, these animals are often implied to have survived to the present day. They somewhat resembled flippered sauropods, but were fish-eaters. Other kinds of classic Mesozoic sea reptiles include the pliosaurs, such as Kronosaurus of Early Cretaceous Australia and Liopleurodon of Late Jurassic Europe (short-necked plesiosaur relatives with massive crocodile-like heads, often thought of as the sea's superpredators during the Jurassic and Early Cretaceous), the mosasaurs like the North American Tylosaurus and European Mosasaurus (giant lizards with fins and tail flukes, with older depictions often being more serpentine, now believed the largest marine predators of the Late Cretaceous seas), and the ichthyosaurs (finned reptiles which resembled dolphins in shape, with sideways-moving tails like fish, usually a dorsal fin, four flippers, and bearing live young rather than laying eggs), specifically the Early Jurassic European Ichthyosaurus (which at only 10 feet long, was quite small compared to some of its relatives, such as the 20 foot Ophthalmosaurus of Late Jurassic Europe and the 30 foot superpredator Temnodontosaurus of Early Jurassic Europe). Some flying and sea reptiles are visible in the Crystal Palace Park of London. An oversized, outdated ichthyosaur and a long-necked turtle-shelled plesiosaur fighting in Jules Verne's classic novel Journey to the Center of the Earth inspired other popular marine reptiles representations, and established the "sea reptile battle" trope in media of the day, more broadly demonstrating that one of the main draws of prehistoric life seems to be seeing them fight. Lesser-known aquatic reptiles that occasionally pop up in fiction include Nothosaurus (a plesiosaur ancestor from the Late Triassic with near-cosmopolitan distribution), Mesosaurus (a meter-long crocodile-like reptile from the Early Permian in Africa and South America, predating the dinosaurs and being the oldest known marine reptile), Tanystropheus (an archosaur relative from the Middle Triassic famed for its preposterously long neck, which it used like a fishing rod), Placodus (a shellfish-eating Middle Triassic reptile resembling a large lizard), Champsosaurus (a crocodile-like reptile from Late Cretaceous North America that actually managed to survive the asteroid that killed the non-avian dinosaurs), and basal ichthyosaurs like the tiny Mixosaurus and the huge Shonisaurus (respectively Middle and Late Triassic animals, both lacking the developed tail and dorsal fins of the Jurassic species).
3. Ichthyosaurs (order Ichthyosauria) are uncommon, but not rare. When they do appear, they are treated as the prehistoric equivalent of dolphins. Interestingly, Ichthyosaurs used to be much more common in fiction in the 19th and early 20th centuries, before being upstaged as the most iconic prehistoric animals by other marine reptiles as well as dinosaurs. Ichthyosaurus is usually the only species that gets named.
4. Plesiosaurs (order Sauropterygia) will always be Elasmosaurus (if they're even named) or some generic over-sized pliosaur labeled Liopleurodon or Kronosaurus. Similar to pterosaurs, they will usually be called "aquatic dinosaurs". Good luck finding a nothosaur, pachypleurosaur or placodont.

Other

1. If it's a turtle (order Testudines), prepare to see either a cute, generic pond turtle, a sea turtle, or a tortoise (and there are only two kinds of tortoise: giant and not-giant). They're also likely to be called amphibians (freshwater turtles are amphibious, or semi-aquatic, but not amphibians). Prehistoric works will sometimes feature a cameo by Archelon, because, well, it's a sea turtle the size of a four-door.
2. Paleozoic reptiles (orders Captorhinida, Mesosauria and Araeoscelidia) do not exist. At all.
3. There were several bizarre extinct groups of reptiles, but most of them were probably never depicted in fiction. Good luck finding a rhynchosaur, choristoderan, drepanosaur, or a procolophonid, among many others.
4. Relatives of modern reptiles, such as giant turtles like Archelon from the shallow seas of Late Cretaceous North America and giant crocodiles like Deinosuchus (Late Cretaceous North America) and Sarcosuchus (Early Cretaceous North Africa) are often included, although they're rarely talked about as much, since they're seen as simply bigger versions of their modern kin. Lizards and snakes get very little mention, although a few post-Cretaceous animals like the giant constrictor snake Titanoboa of Colombia and the giant monitor lizard Megalania of Australia (the latter of which lived recently enough that it's believed to have hunted early humans!) have started to become somewhat popular. Mesozoic true birds also get little mention (remember that all birds technically are dinosaurs, and thus reptiles, as well), but if they do, the ones you're most likely to see are the flying Ichthyornis and the non-flying Hesperornis, both Real Life Toothy Birds from the seas of Late Cretaceous North America. Archaeopteryx (see above) will sometimes be shown as "the first bird", although more recent science suggests it was simply one of many small, feathery dinosaurs.
5. Other reptiles or near-reptiles could appear once in a while — Hylonomus (the earliest known reptile, from Late Carboniferous Canada), Scutosaurus (a large armored herbivore from Late Permian Russian once thought to be ancestral to turtles), Coelurosauravus (a gliding reptile from Late Permian Madagascar), Longisquama (a lizard-like animal of uncertain affinities from Middle Triassic Central Asia, famed for the flamboyant feather-like appendages growing from its back), Hyperodapedon (a widespread hook-billed Late Triassic herbivore belonging to a group of archosaur relatives called Rhynchosaurs), Postosuchus (a huge carnivorous Late Triassic North American archosaur on the evolutionary line to crocodiles, being contemporary to the early dinosaur Coelophysis), Desmatosuchus (an armored herbivorous crocodile-line archosaur with shoulder spikes, likely to protect it from its neighbour Postosuchus), Euparkeria (a small archosaur ancestor from Middle Triassic South Africa), Lagosuchus (a dinosaur ancestor from Late Triassic South America), and others. These animals would either be placed alongside dinosaurs and pterosaurs to give them competition and show how "superior" the latter two are, or could be placed in a setting which focuses on the Permian and Early Triassic period to show the audience a glimpse of the life before the rise of dinosaurs.

Synapsids

Non-mammalian synapsids

1. Outside documentaries, you will never ever see someone refer to a non-mammalian synapsid (formerly united as the orders Pelycosauria and Therapsida, but now scattered across various unranked clades; not true reptiles, but placed here for convenience), regardless as to how cool they might be. The single exception to this has been Dimetrodon, which is frequently shown coexisting with dinosaurs and even labeled as dinosaur itself. Another exception is starting to be made for gorgonopsians, though Primeval is the primary work using them.
2. Dimetrodon, a sail-backed, lizard-like carnivorous proto-mammal (formerly called "mammal-like reptiles") that in North America lived before the dinosaurs, in the Early Permian Period — not far before the greatest mass-extinction of all times, the one that divides Paleozoic from Mesozoic. Like pterosaurs and sea-reptiles, it's often wrongly classified as a true dinosaur or a true reptile in popular media because of its shape, and often wrongly depicted scaly like an iguana because of this — it was actually naked like a frog. Other Permian proto-mammals, like Edaphosaurus (an early large herbivore from Early Permian North America that superficially resembles Dimetrodon, though they're not closely related), Inostrancevia (a bear-sized carnivore from Late Permian Russia that was the largest of a highly advanced group of sabertoothed predatory protomammals called gorgonopsians), Moschops (a bulky herbivore from Middle Permian South Africa known for its thick skull, likely used for headbutting contests), and Dicynodon (a small tusked and beaked herbivore from Late Permian South Africa that serves as the namesake of a group of advanced herbivorous protomammals called the dicynodonts) are less-common sights. While most of the protomammals were wiped out in the Permian extinction event, some lived into the Triassic, and can be shown as competitors of the early dinosaurs and archosaurs. The dicynodonts (such as the widespread Early Triassic Lystrosaurus and Late Triassic North American Placerias, the latter of which was a contemporary of the early dinosaur Coelophysis and the archosaurs Postosuchus and Desmatosuchus) were one of them, but there was also the cynodonts, such as Cynognathus and Thrinaxodon (both from Early Triassic Africa), which were very close to mammals, and likely their direct ancestors. Unlike Dimetrodon and the other proto-mammals, cynodonts are usually shown hairy like a mammal in depictions. Lisowicia, described in 2019, is today the biggest known proto-mammal, a dicynodont from Late Triassic Poland as big as an elephant.

Placental Mammals

1. Woolly mammoths (Mammuthus primigenius) and American mastodons (Mammut americanum), usually called the ancestors of modern elephants, though they were only relatives. It should be noted mammoths were true elephants, being from the modern elephant family Elephantidae, while mastodons were technically not (being part of the more distantly related family Mammutidae). They were also distinct animals, though fiction usually treats them as more or less synonymous (in reality, mammoths are bigger and have sloped backs, curving tusks, and differently-shaped teeth compared to mastodons). They are some of the most popular prehistoric mammals in fiction, and often serve as the "face" of the Pleistocene Ice Age. Woolly mammoths are known for their countless exceptionally well-preserved remains, including hair and even still-edible meat. Often shown as bigger and more "primal" than their modern kin, although they were actually around the same size and nearly identical in terms of behavior. Earlier, less-common relatives of mammoths and American mastodons in media included gomphotheres like the Miocene Platybelodon (known as the shovel-tusker for its spade-like jaws), European mastodons like the Pliocene Anancus (known for its extremely long and straight tusks), deinotheres like the immense Pliocene Deinotherium (or hoe-tusker for the downward-pointing tusks growing from its chin), or the tapir-like small ancestral Moeritherium of Eocene North Africa.
2. Sabertoothed "tigers". Likewise, often portrayed as the ancestors of modern cats, when they were only relatives, and not really tigers, they are more closely related to each other than they are to extant feline species, thus more correctly termed "sabertoothed cats" — or even Smilodon if you're feeling particularly scientific. Their exact killing technique is still controversial among experts, as the iconic sabers were actually quite brittle, and would need to be very carefully deployed, but the popular theory is that they used them to pierce the windpipes of large, thick-skinned animals quickly and efficiently. Other than Smilodon there were other long-toothed felines in prehistory, like the Miocene Machairodus, and even pseudo-felines ^note  Animals that resembled cats but were not actually related like the Oligocene Eusmilus of rope and the Pliocene marsupial Thylacosmilus of South America (see below). Both mammoths and sabertooths (or sabretooths if you're from Commonwealth-speaking countries) have left hundreds of specimens.
3. Ground sloths, most iconically the South American Megatherium, which looked a little like a bear the size of an elephant or a mammoth, and was one of the biggest land mammals ever. It was even able to rear up on its hind legs to reach tree foliage with its massive claws, and was as tall as a T. rex when erect. Sometimes shown as omnivorous, athough there is no evidence for this. The smallish North American ground sloth Megalonyx was first discovered by President Thomas Jefferson in the late 1700s, and initially believed to be a lion. A few of the ground sloths also possessed osteoderms — bony, scale-like structures on the skin, which would have made a handy natural armour, which — together with their prodigious claws — would have helped defend against predators. Both of these animals existed during the Pleistocene Ice Age, although their lineage is far older.
4. Macrauchenia (a camel-like running herbivore often shown with a short, tapir-like trunk) and Toxodon (a superficially rhino- or hippo-like animal) were unusual hoofed herbivores from a uniquely South American lineage of ungulates that weren't closely related to any modern ungulate groups, having no living relatives. Both lived on the Pampas of South America during the Pleistocene Ice Age, and may have even been around to see the first humans enter the continent.
5. Glyptodonts such as Glyptodon and Doedicurus, car-sized herbivorous armadillos that lived during the Pleistocene epoch in South America. They had heavy shells on their backs, and some, such as Doedicurus, also had mace-like tails. They are often cited as examples of convergent evolution with some dinosaurs like the stegosaurs and especially the ankylosaurs.
6. Woolly rhinoceroses, specifically the European Coelodonta antiquitatis and the Siberian Elasmotherium sibiricum. The first had two horns and was the size of modern rhinos, the second was one-horned and elephant-sized. They were basically the ceratopsians of the Ice Age. Coelodonta has left exquisite remains including frozen hairy skin; the Elasmotherium horn is unknown but could have been bigger than a adult human. Also of the same period were the giant non-woolly mammoths like the North American Columbian mammoth (M. columbi), giant straight-tusked elephants like Palaeoloxodon namadicus of Asia, and dwarf insular elephants like P. falconeri of Sicily and Malta (related to P. namadicus). The latter was smaller than a human, and could have given rise to ancient Greek legends likes the Cyclops. Elasmotherium has been hyped up by some as the origin of the Unicorn myth, earning it the popular nickname of the "Siberian unicorn".
7. Prehistoric true bears, specifically the cave bear (Ursus spelaeus) and the short-faced bear (Arctodus simus), which are often confused with one another in fiction. Native to Ice Age-era Eurasia, cave bears are named after the fact that their remains are usually found in caves, and have led to the use of putting "cave" before the name of a modern kind of animal as a semi-common Ice Age form of Whateversaurus (see the cave lion, below). Cave bears have often been depicted as the archenemies of ancient humans in media, usually fighting over the caves themselves. Short-faced bears lived in North America at the same time and were absolutely huge (10 feet tall on their hind legs), possessing short skulls like pit bulls. Traditionally they were believed to have a largely carnivorous diet (as opposed to the mostly vegetarian cave bear), though more recent research has indicated they were more likely opportunistic omnivores similar to today's grizzlies and black bears. The present-day spectacled bear of South America is in fact a close relative of the short-faced bear.
8. Dire wolves (Aenocyon dirus), often portrayed as a bigger and stronger version of the living grey wolf (Canis lupus) despite not being a particularly close relative (they were once thought to be closely related, but genetic studies have recently revealed dire wolves to be part of a more primitive lineage of canids; however, popular culture has yet to catch on). More rare sights are Eurasian cave lions, American lions (both often believed mane-less), and Eurasian cave hyenas. More ancient of all these were amphicyonids (the so-called "bear-dogs") and the nimravids(or "pseudo-cats"), the first lineages of large apex carnivoran predators. Also of note are the creodonts like Hyaenodon, which were not true Carnivora, but only relatives. Despite its name, Hyaenodon was not related to hyaenas, although it did have similiar teeth.
9. Among extinct primates, other than the direct human-ancestors, the Asian orangutan relative Gigantopithecus ("giant ape") is the biggest known ape ever, and is famous because is classically linked with the Bigfoot, Sasquatch, and Yeti legends. It lived in during the Pleistocene and may have even encountered some of our early ancestors.
10. Megaloceros giganteus or the Irish elk, which despite the name, was more closely related to the fallow deer. Known for the huge, man-sized antlers of the adult males, and, naturally, common in Ireland, although it was found as far as Spain and China. The Miocene Synthetoceras of North America and the Pleistocene Sivatherium of India and Africa were not related with it, despite their similar look. The sivathere was an early giraffe with short neck and pseudohorns like a moose, while the synthetoceras was a basal artiodactyl with three horns arranged on its head in a Triceratops-like fashion (one long and two-forked on its nose, and two shorter and not-forked at the top of its head).
11. Other herbivorous mammals that can appear in media are prehistoric horses like the Oligocene Mesohippus and the Pliocene Hipparion, the six-horned and sabertoothed uintatheres, the fork-nose-horned brontotheres (both Eocene and among the first giant mammals, the latter being distantly related to rhinos and the former being of unclear affinities), the strange-horned Arsinoitherium of Oligocene Africa (which was most closely related to elephants despite appearances), and the huge giraffe-like Oligocene Asian rhino relative Paraceratherium (sometimes called Indricotherium or Baluchitherium). More basal and generic-looking were early Eocene North American ungulates like Eohippus (the famous horse ancestor) and Phenacodus. Paraceratherium rivalled against the biggest mammoths and extinct elephants (aside from Palaeoloxodon namadicus which may have been even more massive) as "the biggest land mammal of all times", being three times heavier than a Tyrannosaurus or an African Elephant — the bulk of a medium sauropod dinosaur.
12. Basilosaurus cetoides and Lyviatan melvillei, two massive predatory cetaceans, also lived before the Ice Ages (the former in the Eocene and the latter in the Miocene). The first, a more primitive type of whale, is often cited as an example of misnamed animal because of its '-saurus' suffix (meaning "reptile" or "lizard", which is what the fossils were originally mistaken for) and is sometimes known by the alternate name "Zeuglodon". The second, a relative of the sperm whale, owes its name to the biblical Leviathan and to Herman Melville, who is best remembered for a very famous novel about a very violent whale.

Marsupial Mammals

1. Diprotodon and Procoptodon were two giant herbivorous marsupials of Pleistocene Australia (the first looked like a wombat the size of a rhinoceros, the second was a giant rabbit-faced kangaroo that didn't hop), possible prey of the meat-eating "marsupial lion" Thylacoleo carnifex, which had fanglike incisors — while the marsupial pseudo-sabertooth Thylacosmilus atrox was South American and lived earlier in the Pliocene.
2. Small extinct mammals rarely show up as anything more than an afterthought, even though some, like Didelphodon, have recently become rather popular. Generally, we want our palaeofauna to be big and spectacular and "monstrous", rather than small and cute.
3. The Thylacine (Thylacinus cynocephalus), aka the "Tasmanian wolf" (or "Tasmanian tiger" for its stripes), a superficially dog-like marsupial that is generally agreed to have gone extinct in the 1930s, although there have been a few reported sightings of them more recently, making surviving thylacines essentially a kind of cryptid. Because the aboriginal people of Tasmania and mainland Australia were able to coexist with these animals for millennia, while British settlers wiped them out within a few generations, the thylacine has become a symbol of the irreparable harm that colonialism can do, the fragility of an isolated ecosystem, and the need for active conservation programs.

Other prehistoric organisms

Protostomes

1. Trilobites, which were ancient sea-dwelling arthropods that lived long before the dinosaurs, in the Paleozoic Era. Often mistaken for insects or crustaceans in pop-culture, but they were actually more primitive than both groups, being most closely related to horseshoe crabs and spiders. Trilobites were harmless animals, but well-protected against enemies (some could roll in a ball like woodlice), including some of the first complex eyes on the planet, like those of insects. Coming in a staggering variety of appearances and lifestyles, they dominated the Paleozoic marine fauna for about 270 million years before finally being annihilated at the very end of the Permian period in the biggest ever extinction event in Earth's history.
2. Ammonites, which were marine cephalopods with spiral shells that lived mostly during the time of the dinosaurs, in the Mesozoic Era (although they first appeared in the Paleozoic). They primarily fed on plankton and other tiny prey items and swam by floating like miniature submarines; some fossils also preserve ink, showing they could squirt ink for protection. Modern cephalopods are not strictly related with them, despite the nautilus being similar in shape to an ammonite, with an equally concamerated shell for buoyancy. A ubiqtuous part of Mesozoic marine fauna, they came in a dizzying variety of forms, but were all ultimately wiped out in the same end-Cretaceous extinction vent that took out the non-avian dinosaurs. Belemnites (very similar to squid) and nautiloids (with shells like ammonites, although not always spiralled) are less-frequent extinct cephalopods in media: the former evolved and thrived in dinosaur times (and were also wiped out by the asteroid), while the latter (which predate the dinosaurs by 260 million years) have survived to our days in the shape of the nautilus.
3. Meganeura, a hawk-sized dragonfly relative that lived before the dinosaurs — more precisely, in the Carboniferous Period — together with another "eura", the man-sized millipede relative Arthropleura, the largest terrestrial arthropod to have ever lived (and thankfully, a herbivore). More rare are the eurypterids, (also called "sea scorpions") like the crocodile-sized Pterygotus (of the Late Silurian), which were among the top predators of the Paleozoic seas, being somewhat related to modern scorpions but more similar to free-swimming lobsters than land scorpions in look. Also of somewhat decent popularity is the extremely early (Middle Cambrian, approximately 500 million years ago) marine arthropod-relative Anomalocaris, which looks superficially like some kind of large shrimp at a first glance and is known to have been one of the first apex predators to have ever evolved.

Fish

1. Megalodon (Charcarocles megalodon, or Otodus megalodon, depending on who you ask), a giant shark (30-60 feet, depending on the estimate) similar in look to the Great White, that lived well after the dinosaurs, in the Cenozoic Era. It dominated Cenozoic oceans for 20 million years and hunted whales, although its size is often exaggerated in media to well over a hundred feet, and is often wrongly implicated to be still-living somewhere in our oceans. Another giant superpredatory fish — the placoderm Dunkleosteus — is rarer in media, but it's noted for its heavy armor, scissor-like "teeth" (actually sharpened plates of bone), and having lived before the dinosaurs, in the Devonian Period. In the same period lived Eusthenopteron, one of the ancestors of land vertebrates; tiny armored fish named ostracoderms; and many other fishes, to the point that the Devonian is often called the Age of Fish.

Amphibians

1. Prehistoric amphibians (not the ancestors of the modern ones, but those belonging to extinct groups, such as the Temnospondyls, aka Labyrinthodonts) like Ichthyostega (from Late Devonian Greenland), Diplocaulus, Eryops, or Seymouria (all from Early Permian North America) can sometimes be thrown in for good measure. However, there's a huge chance they will be inaccurately depicted as living alongside dinosaurs, when in reality, most of the extinct lineages of amphibians died out long before the first dinosaurs appeared. One of them, the European Middle Triassic temnospondyl Mastodonsaurus, was 20 feet long and one of the biggest amphibians ever; it is portrayed at the Crystal Palace Park, albeit as a frog-like animal when we now know it to be more like a tusked newt/crocodile mix. Ichthyostega was one of the first vertebrates with legs (and still very fish-like in some ways), Diplocaulus had a strange boomerang-shaped head, Eryops was a temnospondyl that was a bit like a gator in shape, and Seymouria was a largely terrestrial animal with dry skin like a reptile. The 15 foot long temnospondyl Koolasuchus was the very last of these ancient amphibians, living in Australia during the Early Cretaceous alongside the dinosaurs.

Plants

1. Prehistoric plants usually act as simple background elements in stories, and are usually unnamed. They tend to look more often like palms, ferns, or cycads (like in the picture above, which shows also the classic erupting volcano), more seldomly to normal-looking trees like the magnolia, ginkgo trees, or conifers like redwood, monkey-puzzles, pines/spruces, jews etc. Giant lycopods and horsetails, despite their cool look, are seen usually only in documentaries, despite the lycopods being the most striking and exotic plant elements of the "Coal Age" (the Carboniferous, before the Mesozoic). Expect also to see grasslands at dinosaur times, even though grass started to grow into true prairies only in the most recent half of the Mammal Age, 15 mya.

Unicellular organisms

1. Extinct unicellular organisms are virtually unknown in fiction: the ones seen in Disney's Fantasia are modern water organisms, both one- and multi-celled, and not prehistoric at all. In documentary media, however, you have chances to see the Foraminifers (eukaryotic and shelled) mainly because are linked with the dinosaur extinction argument, and the Stromatolites (rocky marine structures made by photosyntetic bacteria), because are the most ancient known living beings to science, hailing from 3 billions years ago. Both groups of organisms are still-living today.

No examples, please. This only defines the term.

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