Follow TV Tropes


Useful Notes / Prehistoric Life

Go To

"Those animals of other days will give joy and pleasure to generations yet unborn."
Charles H. Sternberg

This page is all about prehistoric life, listing many species of extinct creatures, from plants to non-human hominins. Of course dinosaurs receive more details than the other groups, but it would be a really, really incomplete list without non-dinosaurs.

Important: This page is only about non-stock animals: that is, creatures that may appear in popular-science works but have never been portrayed in film, comics, or novels, or at least, have been portrayed only occasionally. The vast majority of dinosaurs are in this category, yet they are just as cool as their more famous relatives. If you want to read about the most popular extinct animals, dinosaurs and otherwise, there is already good information here and here.

To help you:

    Time Scale 

The geologic and biological history of the Earth is divided into four eons: the Hadean, Archean, Proterozoic, and Phanerozoic. Each eon is divided into eras, which are themselves subdivided into periods, which are in turn infradivided into epochs. Since we know a heck of a lot more about the recent past than we do about the very very ancient past,note  the first three eons are sometimes grouped together into a single “supereon” known simply as the Precambrian.

PRECAMBRIAN: Earth before 542 million years ago.

  1. Hadean eon: Starting from the formation of the Earth 4.6 billion years ago, and lasting until the Earth cooled, solidified, and generally calmed down enough that fossilized bacteria could form. The Hadean eon as it was first conceived began with Earth congealing from space dust and ended with the first rocks that survived to the present formed; before that, Earth’s crust was thought too unstable to leave geological evidence. However, some miraculously surviving rock samples from the Hadean were found in Greenland, necessitating the change in definition. Previously it was thought that Earth was super-volcanic during this eon; the current scientific consensus states that no, neither volcanism nor tectonics nor the planetary dynamo had begun for most of the Hadean era. The total meltdown of Earth that caused the formation of core, mantle and crust and the start of volcanism and plate tectonics marked the transition from the Hadean to the Archean.
  2. Archean eonnote : Starting 3.8 billion years ago, and lasting until oxygen started to build up in the Earth’s atmosphere 2.5 billion years ago. This atmospheric oxygen was created by cyanobacteria, and spelled instant death for any life that couldn’t evolve aerotolerance. It was the worst case of air pollution in the Earth’s history.
  3. Proterozoic eon: Starting 2.5 billion years ago, and ending a scant 542 million years ago with the Cambrian Explosion. This eon saw the emergence of the first eukaryotic life forms (cells with a nucleus) 1.6-2.1 billion years ago, the first sexually reproducing organisms 1-1.2 billion years ago, and the first multicellular organisms. The final era of this eon was:
    • Neoproterozoic era: Starting 1 billion years ago. At the onset of this era, a supercontinent named Rodinia straddled the Earth’s equator. Ice ages came and went which were so severe that the ice sheets reached all the way to the equator, resulting in a “Snowball Earth”. Rodinia eventually broke up, only to reform as a different supercontinent named Pannotia. The final period of this era was:
      • Ediacaran periodnote : Starting 635 million years ago, and marked the “Dawn of Animal Life”. Or so we think. In any case, multicellular life that probably (but not certainly) belongs to the kingdom Animalia first appeared around 580 million years ago; possible fossils are found even earlier, near the beginning of the period, but nothing conclusive. Many possible ancestors of known invertebrate groups show up in the record, including comb-jellies, sponges, corals, anemones, and molluscs, and one fossil might even be a chordate (vertebrate ancestor). Fungi also emerge during this period.

PALEOZOIC ERA: Earth from 542 million years ago to 251 million years ago.

  1. Cambrian period: The “Explosion of Life”. Most of the main invertebrate groups appeared, as well as the first certain vertebrate ancestors. Life was still water-exclusive. (Probably.) Graptolites, cephalopods, and chitons emerge during this period. The first predators appear and cause evolution to speed up drastically, resulting in the Cambrian Explosion.
  2. Ordovician period: First true fish appeared. Arthropods ventured onto land. Ended with a mass extinction.
  3. Silurian period: First jawed fish and later ray-finned fish appeared. Plants and scorpions started to colonize dry land. Also home to the eurypterids ("sea scorpions").
  4. Devonian period: The Golden Age of Fishes. The first four-limbed vertebrates appeared. Insects, crabs, ferns, and sharks evolved. Ended with a mass extinction.
  5. Carboniferous period: Forests spread around the world. The Golden Age of Insects and Amphibians. Sharks reached large sizes, and ratfish, amniotes, synapsids, diapsids, and hagfish evolved.
    In the United States, rocks from the Carboniferous Period are so plentiful that scientific community has allowed geologists there to divide it into two:
    1. Mississippian period: This period, which is called the Lower Carboniferous elsewhere in the world, saw a major rebound in diversity from the mass extinction that ended the Devonian. This paved the way for the life-forms of the next period:
    2. Pennsylvanian period: This period, which is called the Upper Carboniferous elsewhere in the world, contains the massive coal deposits (actually the remains of vast swampy forests) that give the Carboniferous its name.note 
  6. Permian period: The supercontinent of Pangaea formed, and Earth became more arid. The Golden Age of Mammal-like Reptiles. Beetles and therapsids evolved. Temnospondyls and pelycosaurs diversified. Ended with the worst mass extinction ever.

MESOZOIC ERA: Earth from 251 million years ago to 66 million years ago.

  1. Triassic period: Seed plants diversified. True reptiles replaced mammal-ancestors. Most of the main groups of land vertebrates still alive today appeared, dinosaurs and mammals are among them. Many groups that did not leave modern descendants, such as pterosaurs and many marine reptile groups, evolved as well. Ended with a mass extinction.
  2. Jurassic period: Dinosaurs became the largest and most diverse land vertebrates, and some became fliers (including possible proto-birds). New types of pterosaurs and marine reptiles evolved. The three still-living mammalian groups (monotremes, marsupials, and eutherians/placentals) appeared.
  3. Cretaceous period: Dinosaurs further diversified, and the first dinosaurs that are universally recognized as birds appeared. Flowering plants and several groups of insects coevolved, creating the most common terrestrial ecosystem around today. Modern groups of fish evolved. Despite the movie’s name, most of the dinosaurs shown in Jurassic Park flourished in the Cretaceous period, not the Jurassic period note . Ended with the last mass extinction up to the present, known as the K-Pg Extinction Event.note 

CENOZOIC ERA: Earth from 66 million years ago to the present day.

  1. Paleogene period: consisted of the Paleocene, Eocene and Oligocene epochs. Mammals underwent an explosive evolution, and most still-living lineages appeared, primates included. Birds, crocodilians, turtles, squamates and lissamphibians were the other terrestrial vertebrates to survive the mass extinction. At the end of this period, the Earth started to become colder, and polar ice caps started to form.
  2. Neogene period: consisted of the Miocene and Pliocene epochs. Continents acquired their modern placement, and new mountain ranges appeared. Grasslands became a widespread environment, partially replacing forests. New kinds of mammals appeared, among them the first hominids.
  3. Quaternary period: consists of the Pleistocene and the current Holocene epoch. Started 2.59 million years ago. Several Ice Ages alternated with interglacial periods. All modern species of plants and animals were already present, as well as many now-extinct species, most of which were killed off by humans. Truly modern humans evolved late in the Pleistocene, and all modern behaviors were fully developed before the onset of the Holocene, which includes all of human history from the earliest proto-civilizations to the present.note  The only surviving human species, Homo sapiens sapiens, has become a major influence on the environment worldwide.

The first written records began to appear some 5000 years ago, which marked the beginning of recorded history. Anything more recent than that ain’t prehistoric.

    Translation Guide 

When reading the examples, you’ll notice that you can place many prehistoric critters into their correct groups with much confidence simply by observing their hallmark suffixes. But also note that not all members of each group have their designated suffix; nor are these suffixes necessarily exclusive of these groups (think about the whale Basilosaurus). Usually these suffixes are Latinized Greek, but there are many examples from languages other than Latin and Greek, such as Yutyrannusnote , Azhdarchonote , Tawanote , and Yinote . Perhaps the most famous example of them is Quetzalcoatlusnote . Some names are even English: "Drinker" note , Dreadnoughtus note . Some names come from modern geography: Mosasaurusnote , Edmontosaurus, Albertosaurusnote , Lesothosaurusnote , Mamenchisaurus, Tuojiangosaurusnote , Saltasaurus, Riojasaurusnote , Minmi, Muttaburrasaurusnote , Lisowicianote . Others come from Real Life people's names: Andrewsarchusnote . "Othnielosaurus" note , Herrerasaurus, Alvarezsaurusnote , Scipionyxnote , Leaellynasauranote , Avaceratopsnote , Inostrancevianote .

  1. -saurus: Greek for “lizard”: in paleontology identifies reptiles in general (in the traditional sense of the word), not only dinosaurs. E.g. Allosaurus, Plesiosaurus, Scutosaurus, Edaphosaurus. Often identifies amphibians as well: Mastodonsaurus. The whale Basilosaurus is an exception due to Science Marches On (it was initially believed to be a marine reptile).note  The suffix can also become a prefix: Saurolophus, Sauroctonus, Saurosuchus, the sauropods, and the saurischians. Also attested is the feminine variant -saura: Maiasaura, Leaellynasaura.
  2. -ceratops: Greek for “horned face”. E.g. Pentaceratops, Protoceratops. The most famous dinosaur with this ending is, of course, Triceratops.
  3. -mimus: Greek for “mimic”: mostly identifies small birdlike theropods, particularly ornithomimids (whose names are usually preceded with a bird-related prefix). E.g. Struthiomimus, Gallimimus, Avimimus. Also applied to some larger and smaller dinosaurs; specifically, theropods seem to get this suffix somewhat often, due to their close relation to avian dinosaurs: Suchomimus, Sciurumimus.
  4. -raptor: Latin for “thief”, “plunderer” or “robber”: since the success of Jurassic Park, identifies mainly dromaeosaurids (Pyroraptor, Bambiraptor), but many other theropod dinosaurs are named this as well: Oviraptor, Gigantoraptor, Megaraptor, Fukuiraptor. Birds of prey are also commonly called raptors, but no genus of avian dinosaur contains this suffix in its name.
  5. -tyrannus: Greek for “tyrant”. Often given to tyrannosaurids. E.g. Sinotyrannus, Yutyrannus. -venator (Latin for "hunter") can be sometimes applied to theropods. E.g. Microvenator, Neovenator.
  6. -titan: Often given to giant sauropods such as Giraffatitan and Paralititan. Also applied to some hadrosaurs, such as Olorotitan, and to some theropods, such as Tyrannotitan.
  7. -pelta: Greek for “shield”. Very common in ankylosaur names. E.g. Sauropelta, Borealopelta, Aletopelta.
  8. -cephale: Greek for “head”. Typical of pachycephalosaurs. E.g. Homalocephale, Prenocephale.
  9. -dactylus: Greek for “finger” or “digit”. Typically identifies pterosaurs, from the namesake Pterodactylusnote . E.g. Cearadactylus, Preondactylus, Araripedactylus.
  10. -suchus: Greek for “crocodile”. In paleontology identifies true crocodilians, crocodile-like reptiles, or crocodile-like amphibians. E.g. Deinosuchus, Titanosuchus, Koolasuchus, Prionosuchus. Also meaning “crocodile” is champsus/a: Pristichampsus, Proterochampsa. Champsosaurus means “crocodile lizard”.
  11. -therium: Greek for “beast” or “wild animal”. Most prehistoric mammals have this—the famous documentary Walking with Beasts was so named in reference to the countless -theriums here. E.g. Uintatherium, "Baluchitherium", Chalicotherium, Arsinoitherium, Deinotherium, Sivatherium, Moeritherium. But perhaps the most famous example is Megatheriumnote . Several -sauruses have their -therium counterpart, too: Brontosaurus - "Brontotherium"; Stegosaurus - Stegotherium; Elasmosaurus - Elasmotherium; Megalosaurus - Megatherium; Ceratosaurus - Ceratotheriumnote . Ther- has the same meaning and is the prefix of two important groups of animals: the theropods and the therapsids. Fulgurotherium is an exception, being a dinosaur.
  12. -felis: Latin for “cat”. Applied to extinct felids or pseudo-felids quite a bit of the time. E.g. Dinofelis, Barbourofelis. -smilus (meaning “knife”) can indicate sabretooths or pseudo-sabretooths: Eusmilus, Thylacosmilus.
  13. -cyon, cyno-: Greek for “dog”. Applied to extinct canids and other doglike mammals. E.g. Hesperocyon, Cynodictis. Some therapsid names have this suffix as well due to their superficial resemblance to dogs: Cynognathus and its group, the cynodonts (and also their relatives, the dicynodonts).
  14. -hippus: Greek for “horse”. Almost every animal in the equid lineage ends in this way. E.g. Pliohippus, Merychippus, Mesohippus. Some horse ancestors have this as a prefix: Hipparion, Hippidion. Also the common name of a well-known modern animal (the hippopotamus, meaning “river horse”) has it as prefix.
  15. -cetus: Greek for “sea-monster”. Extinct cetaceans can have this in their name. E.g. Pakicetus, Ambulocetus, Cetotherium, Odobenocetops.
  16. -pithecus: Greek for “monkey”. The hallmark of most prehistoric primates, human ancestors included. E.g. Aegyptopithecus, Oreopithecus, Pliopithecus, Gigantopithecus, Australopithecus.
  17. -ornis and -avis: Greek and Latin (respectively) for “bird”. Denotes... guess. E.g. Osteodontornis, Icthyornis, Anthropornis, Dinornis, Argentavis, Avisaurus. When used as a prefix, “-ornis” becomes ornitho-: Ornithomimus, Ornithosuchus, the ornithopods, and the ornithischians.
  18. -chelon, chelys: Greek for “turtle” or “tortoise”. Denotes... guess. E.g. Archelon, Colossochelys.
  19. -batrachus: Greek for “frog”. Several ancient amphibians (not only frogs) have this. E.g. Triadobatrachus, Paleobatrachus, Peltobatrachus.
  20. -ichthys: Greek for “fish”. Indicates many fish, i.e. non-tetrapod vertebrates. E.g. Leedsichthys, Saurichthys. Ichthyosaurus, Ichthyostega and Icthyovenator are non-piscine examples.
  21. -aspis: Greek for “shield”. Almost all names of ostracoderms and some placoderms (both armored fish) have this suffix. E.g. Pteraspis, Cephalaspis, Drepanaspis, Lunaspis, Astraspis.
  22. -ceras: Greek for “horn”. Many nautiloids and ammonoids (shelled cephalopods) have this, due to their horn-shaped shells. E.g. Orthoceras, Rayonnoceras, Dactylioceras.
  23. -pteris: Greek for “fern”. Many extinct fernlike plants end with this. E.g. Archaeopteris, Glossopteris.
  24. -ite: This suffix is typical for minerals, but has also been applied to some fossil groups (since fossils and rocks have always been associated with each other): more famously the Ammonites and the Trilobites, but also the Belemnites, the Graptolites, all invertebrates. Also, the protozoan Nummulites (typical of early Caenozoic) and the microscopic algae Coccolites (very common in the Cretaceous).

There also suffixes that do not indicate a specific groups of animals, but mark anatomical traits instead:

  1. -odon/-odonto-: Greek for “tooth”. Animals with notable teeth (or that are known mainly by their teeth) can get names containing this. E.g. Heterodontosaurus, Thecodontosaurus, Carcharodontosaurusnote . Mammalian example are Smilodon and Glyptodon. Other examples: Iguanodon, Hypsilophodon, Troodon, Dimetrodon, Dimorphodon, Megalodon, the Conodonts. A deceptive case is Pteranodon, which actually means “winged with no teeth”. Less-frequent is the variant -odus, with the same meaning: Placodus, Hybodus, Phenacodus.
  2. -ceras/cerato-/-ceros/-ceroto-: Greek for “horn”. Guess what prominent feature these creatures bear. E.g. Megaloceros, Teleoceras, Ceratosaurus. Also the common name of a famous modern animal: the rhinoceros of course (meaning “horned nose”).
  3. -lophus/lopho-: Greek for “crest”. Indicates animals with some sort of crest. E.g. Parasaurolophus, Dilophosaurus, Tetralophodon. Corytho- and corypho- have similar meanings: Corythosaurus, Coryphodon.
  4. -cephalus/-cephalo-: Greek for “head”. E.g. Euoplocephalus, Cistecephalus, Planocephalosaurus, Caulkicephalus.
  5. -rhinus/rhino-: Greek for “nose”. Critters with something prominent on their noses often have this. E.g. Altirhinus, Pachyrhinosaurus, Eurhinodelphis, Dicerorhinusnote .
  6. -rhynchus/rhyncho-: Greek for “beak”, but also “muzzle”. E.g. Rhamphorhynchus, Metriorhynchus, Rhynchosaurus, Rhynchippus.
  7. -gnathus/gnatho-: Greek for “jaw”. E.g. Compsognathus, Cynognathus, Batrachognathus, Gnathosaurus, Pristerognathus.
  8. -pteryx/ptero-/-pterus/-pteron: Greek for “wing”, “feather”, but also “fin”. E.g. the winged Archaeopteryx, Pterodaustro, Dsungaripterus; and the fish Eusthenopteron. Also known is the variant pteryg- (indicating fins or fin-like structures): Pterygotus, Stenopterygius, Platypterygius. Actinopterygii and Sarcopterygii respectively mean “rayed fin” and “fleshy fin”.
  9. -onyx/-onychus: Greek for “nail” or “claw”. Animals with one or more enlarged claws in their hand or foot (or mainly known from their claws) have often these suffixes. E.g. Baryonyx, Deinonychus, Hesperonychus, Megalonyx, Scaphonyx, Scipionyx. Alvarezsaurid names end with the variant -onykus: Mononykus.
  10. -spondylus: Greek for “vertebra”. E.g. Massospondylus, Eustreptospondylus, Bothriospondylus, Spondylosoma.
  11. -acanthus/acantho-: Greek for “spike” or “spine”/ Many spiky or spiny critters include this in their name. E.g. Polacanthus, Stethacanthus, Metriacanthosaurus, the acanthodians.
  12. -(h)oplo-: Greek for “armor”, “weapon”. E.g. Panoplosaurus, Dyoplosaurus, Hoplophoneus, Hoplitomeryx.
  13. -ch(e)irus/ch(e)iro-: Greek for “hand”. E.g. Deinocheirus, Austrocheirus, Chirostenotes, "Chirotherium".
  14. -pus/-po-: Greek for “foot”. E.g. Moropus, Astrapotherium, Saltopus, Saltoposuchus, Hallopus.
  15. -pleuro/-pleura: Greek for “side” or “hip”. E.g. Pleurosaurus, Liopleurodon, Pleuracanthus, Arthropleura.
  16. -urus/uro-: Greek for “tail”. E.g. Dacentrurus, Coelurus, Urocordylus, Teinurosaurus. There is also -cercus with the same meaning: E.g. Pholidocercus, Eucercosaurus.
  17. -lepis, lepido-: Greek for “scale”. Many fish have these. E.g. Bothriolepis, Cheirolepis, Leptolepis, Lepidotes. The ancient treelike Lepidodendron means “scaly tree”.
  18. -osteus, osteo-: Greek for “bone”. E.g. Dunkleosteus, Coccosteus, Osteolepis, the Osteostracians.
  19. -oides: Greek for “similar to”, or figuratively, “false”. E.g. Dromaeosauroides, Archaeornithoides, Saurornithoides, Campylognathoides.
  20. -ops: Greek for “eye”, “face”, or “appearence”. E.g. Eryops, Moschops, Megacerops, Dolichorhynchops. “-ceratops” is a composite suffix made of “cerato-” (“horn”) and “ops”.

Common prefixes or suffixes that function as adjectives:

  1. allo-: Greek for “different”. E.g. Allosaurus fragillisnote , Allodontidae.
  2. mono-/di-/tri-/tetra-/penta-/hexa-: Greek for “one/two/three/four/five/six”. E.g. Monolophosaurusnote , Dilophosaurusnote , Triceratopsnote , Tetraceratopsnote , Pentaceratopsnote , Hexameryxnote .
  3. a-/an-: The "privative A". When put in front of a word, indicates the thing in question is missing in the animal. If the word begins with a vowel, the “a” becomes “an”. E.g. Anoplotheriumnote , Pteranodonnote , Aceratheriumnote .
  4. eo-: Greek for “dawn”. Indicates primitive species within a larger group. E.g. Eoraptornote , Eoceratopsnote , Eohippusnote , Eocarcharianote .
  5. eu-: Greek for “good”, “true”, or “well”. E.g. Eusthenopteronnote , Eurhinosaurusnote , Eudimorphodonnote .
  6. pro-: Greek for “before”. E.g. Procompsognathusnote , Proceratosaurusnote , Promastodonsaurusnote .
  7. proto- and protero-: Greek for “the first”. E.g. Protoceratopsnote . Protosuchus and Proterosuchusnote  are distinct kinds of Triassic crocodile-like reptiles.
  8. archaeo-, palaeo-, meso-, caeno-, neo-: The first two meaning “ancient”, the last two “recent” and “new” respectively, while meso means “middle”. E.g. Archaeopteryxnote , Palaeotheriumnote , Mesonyxnote , Caenolestesnote , Neoceratodusnote . The word “palaeontology” means “the study of ancient beings”. There are also the prefixes of the main geological eras (following the older classifications): the Archaeozoic, the Paleozoic, the Mesozoic, the Cenozoic, and the Neozoic.
  9. para-: Greek for “near” or “beside”. E.g. Parasaurolophusnote , Paraceratheriumnote .
  10. coel-: Greek for “hollow”. E.g. Coelophysisnote , Coelurosauravusnote , Opisthocoelicaudianote , Coelacanthusnote , Coelodontanote .
  11. drom-: Greek for “running” or “runner”. E.g. Dromaeosaurusnote , Orodromeusnote , Kulindadromeusnote .
  12. drypto-: Greek for “to tear”. E.g. Dryptosaurusnote .
  13. mega-/megalo-, titano-, and giga-/giganto-: Greek for “big”, “titanic”, and “gigantic”. E.g. Megalosaurusnote , Megalocerosnote , Megantereonnote , Megaraptornote , Wintonotitannote , Titanosaurusnote , Titanoboanote , Gigantophisnote , Gigantopithecusnote , Giganotosaurusnote , C. megalodonnote .
  14. macro- and micro-: Greek for “big”/ “large” and “small”/ “tiny” respectively. E.g. Macrophalangianote , Macrurosaurusnote , Microraptornote , Microceratusnote , Micropachycephalosaurusnote .
  15. diplo-: Greek for “double”. E.g. Diplodocusnote , Diplocaulusnote , Diplocynodonnote .
  16. homo- & hetero-: Greek for “similar” and “different” respectively. E.g. Homotherium,note Heterodontosaurusnote  the Heterostraciansnote .
  17. sarco-: Greek for “meat” or “flesh”. E.g. Sarcosaurusnote , Sarcolestesnote . There is also creo- with the same meaning: creodontsnote .
  18. stego-: Greek for “roof” or “tile”. E.g. Stegosaurusnote , Stegocerasnote , Stegodonnote . The early tetrapod Ichthyostega means “roof fish”.
  19. sino-: Greek for “Chinese”. E.g. Sinornithosaurusnote , Sinosaurusnote , Sinraptornote , Sinodelphysnote .
  20. syn-: Greek for “fused” or “united”. E.g. Synthetocerasnote , "Syntarsus".note ,

And oh, don’t forget these:

  1. bronto-: Greek for “thunder”. E.g. Brontosaurusnote , Brontopsnote , Brontoscorpionote .
  2. dino-/deino-: Greek for “terrible” (but also “ponderous”, “magnificent”; “fearfully great” or “awe-inspiring” was the original intention). E.g. Deinosuchusnote , Dinofelisnote .
  3. gorgo- and terato-: “Gorgo-” is “fierce”: (or can refer to the Gorgon of mythology) in Greek, whilst “terato-” is “monstrous”. E.g. Gorgosaurusnote , Gorgonopsnote , Teratosaurusnote , Teratornisnote .
  4. -long: Simplified Chinese for “dragon”. The most recent stock suffix. Dinosaurs found in China since the 2000s have usually been named with this ending. Examples include Guanlongnote , Bolongnote , Dilongnote  and Tianyulongnote .
  5. -ryu: Japanese for “dragon”. Across The '80s 11 more or less fragmentary dinosaurs found in Japan were unofficially named "Fukuiryu", "Hironoryu" (both ornithopods), "Hishanohamaryu", "Moshiryu", "Sugiyamaryu" (all sauropods), "Futabaryu", "Kagaryu", "Katsuyamaryu", "Kitadaniryu", "Mifuneryu", "Sanchuryu" (all theropods). Then, in 1990, all them were renamed with the classic suffix -saurus, becoming "Fukuisaurus", "Futabasaurus", "Hironosaurus", "Hishanohamasaurus", "Kagasaurus", "Katsuyamasaurus", "Kitadanisaurus", "Mifunesaurus", "Moshisaurus", "Sanchusaurus", and "Sugiyamasaurus". All have not been described yet in official science except for Fukuisaurus,note  and are thus labeled as Nomen nudum (lit. "naked name"); and some are also Nomen dubium (lit. "dubious name") — the latter are those fossils that are too incomplete to be classified correctly. See also here.