Line #55 UsefulNotes/PrehistoricLifeCeratopsidPredecessors


1	----
2
3	[[quoteright:350:https://static.tvtropes.org/pmwiki/pub/images/the_childrens_museum_of_indianapolis___psittacosaurus_skeleton_cast.jpg]][[caption-width-right:350:Dinosaur or Parrot?]]
4
5	Among the chosen examples you can tell the closest-to-ceratopsids apart from the most basal kinds by simply reading their names: the former usually have the suffix -ceratops (ex. ''Zuniceratops'', ''Bagaceratops'', ''Montanoceratops''), the latter usually end in other ways (ex. ''Chaoyangsaurus'', ''Yinlong'', ''Stenopelix''). The animal of the image is a very basal kind, the famed ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Psittacosaurus]]''.
6
7	[[foldercontrol]]
8
9	----
10
11	[[folder:Non-Stock Ceratopsid Predecessors]]
12
13	----
14
15	'''Horned Muzzle?:''' ''[[http://en.wikipedia.org/wiki/Montanoceratops Montanoceratops]]''
16
17	* The semi-bipedal ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Leptoceratops]]'' lived in Late Cretaceous North America together with the quadrupedal ''Montanoceratops cerorhynchos'' ("horned face from [[ExactlyWhatItSaysOnTheTin Montana]] with a horned beak"). The latter was originally classified in the 1940s as a new ''Leptoceratops'' species. Slightly bigger than ''Leptoceratops'', ''Montanoceratops'' was once depicted with a small nasal horn like a miniature ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Centrosaurus]]'': [[ScienceMarchesOn we now know]] it hadn't such a thing -- the bone believed a horn was actually misplaced in the fossil. ''Protoceratops'', ''Leptoceratops'', ''Montanoceratops'', and other animals made once one family, the Protoceratopsids; now ''Leptoceratops'' and ''Montanoceratops'' make their own family, Leptoceratopsids, together with other more recently-found animals such as ''Udanoceratops'' and ''[[http://en.wikipedia.org/wiki/Prenoceratops Prenoceratops]]''.
18
19	----
20
21	'''Tiny but Four-legged:''' ''[[http://en.wikipedia.org/wiki/Bagaceratops Bagaceratops]]''
22
23	* Another protoceratopsid, Asian ''Bagaceratops'', was until recently put in its own family as well: Bagaceratopsids, together with other less-known genera such as ''Breviceratops'' and the unusually European ''[[http://en.wikipedia.org/wiki/Ajkaceratops Ajkaceratops]]''. Found in Mongolia in the 1970s, ''Bagaceratops'' is notable because was one of the smallest quadrupedal dinosaurs that ever lived: only one meter long, shorter than a ''Compsognathus'', yet still a bit bigger than the bipedal ''Microceratus'', it had a particularly short frill and an incospicuous "hornlet" on its nose. Being so vulnerable, ''Bagaceratops'' might have lived in sheltered environments to hidden itself against gigantic predators like the contemporaneous ''Tarbosaurus''. Many new basal ceratopsians have been described since the 1990s both in Asia and in North America; for example, ''[[http://en.wikipedia.org/wiki/Udanoceratops Udanoceratops]]'' (one of the largest, twice longer than a Protoceratops) was close to ''Leptoceratops'' but living in Asia; ''Asiaceratops'' was also an [[ExactlyWhatItSaysOnTheTin Asian]] Leptoceratops-relative; ''[[http://en.wikipedia.org/wiki/Graciliceratops Graciliceratops]]'' ("gracile horned face") was similar to ''Microceratus'', and some alleged "microceratops" remains actually belonged to it; while ''[[http://en.wikipedia.org/wiki/Breviceratops Breviceratops]]'' ("short horned face") was originally considered a second ''Protoceratops'' species. Worthy of note is also ''[[http://en.wikipedia.org/wiki/Koreaceratops Koreaceratops]]'': found in the eponymous Asian peninsula in the first half of TheNewTens, its describer said it was possibly a ''marine'' dinosaur, just like ''Spinosaurus''.
24
25	----
26
27	'''The Earliest American Horns:''' ''[[http://en.wikipedia.org/wiki/Zuniceratops Zuniceratops]]''
28
29	* Differences between Proto-ceratopsids and Real-ceratopsids are considerable. There ''should'' have been at least one intermediate form between the two: how could it have looked? In 1998, the answer was found under the name ''Zuniceratops'' (which has detained the record of “the last member of the Dinosaur Alphabet” for some years). The most ancient North American ceratopsian, from Middle Cretaceous, it was only 4 m long (less than half a ''Triceratops''), and had a mixed ''Triceratops'' / ''Protoceratops'' appearance: two long frontal horns like the former, and none on the nose like the latter. This MixAndMatchCritter look surprised scientists, which used to think frontal horns were a very evolved trait of some advanced ceratopsids - while the nasal one was believed the most ancient horn in ceratopsid’s history. The ancestry of the frontal horns was confirmed in the 2000s, when some early centrosaurine true ceratopsids (the no-frontal-horns subfamily) showed long frontal horns like those of a chasmosaurine, ex. ''[[UsefulNotes/PrehistoricLifeCeratopsids Albertaceratops]]''. Now scientists think later centrosaurines (''Centrosaurus'', ''Styracosaurus'', ''Pachyrhinosaurus'', and so on) reduced secondarily the length of these horns. There was also a chasmosaurine which eliminated its nasal horn, resembling a ''Zuniceratops''; this one is variably classified either as an odd-looking ''Triceratops'' species (''Triceratops hatcheri'', named after John Hatcher, one of Marsh's main collaborators) or a separate genus, ''[[UsefulNotes/PrehistoricLifeCeratopsids Nedoceratops]]'', originally called "Diceratops" ("two-horned face") or "Diceratus" -- the name "Diceratops" was pre-occupied by an insect and had the same fate of "Microceratops".
30
31	----
32
33	'''Ceratopsian?:''' ''[[http://en.wikipedia.org/wiki/Yinlong Yinlong]]''
34
35	* Another, even more important missing-link was found as recently as the 2006: following the current trend about Chinese dinos’ naming, it was called ''Yinlong'' ("hidden dragon"). Living in Late Jurassic, it took the "most primitive ceratopsian" record away from ''Psittacosaurus''. Its external appearance was the least ''Triceratops''-like one can imagine: ''Yinlong'' was not only totally bipedal, but had neither any parrot-bill, nor spiky cheeks. Its only ceratopsian trait is a merely anatomical one: the “rostral bone” at the tip of its upper jaw, present in all ceratopsians and in no other dinosaur group. To compensate, ''Yinlong'' had small “canines”: this, together with its size (4 ft long) and shape, makes it quite similar to the basal ornithischian ''[[UsefulNotes/StockDinosaursOrnithischianDinosaurs Heterodontosaurus]]''. Indeed, this resemblance was once cited as the definitive proof that heterodontosaurids were not ornithopods but ancient relatives of ceratopsians and pachycephalosaurs, but now the latter is disputed. Among the other intermediate forms, ''[[http://en.wikipedia.org/wiki/Turanoceratops Turanoceratops]]'' from Central Asia was perhaps close to ''Zuniceratops'' and maybe one of the ceratopsids' ancestors. But others guys have revealed to be more primitive than ''Protoceratops'' or ''Leptoceratops'', if not at the same degree of ''Yinlong''. Two of them have become the namesakes of their own family: the Early Cretaceous ''[[http://en.wikipedia.org/wiki/Archaeoceratops Archaeoceratops]]'' ("ancient horned face"), was a sort of middle-way between ''Psittacosaurus'' and ''Leptoceratops'' - the same about ''[[http://en.wikipedia.org/wiki/Auroraceratops Auroraceratops]]'' "dawn horned face", which had an unusually-shaped skull; the second is the Late Jurassic ''[[http://en.wikipedia.org/wiki/Chaoyangsaurus Chaoyangsaurus]]'' (originally called "Chaoyoungosaurus" or "Chaoyangosaurus"). Described in 1983, ''Chaoyangsaurus'' (and its closest relative ''Xuanhuaceratops'', originally named "Xuanhuasaurus" in 1986) initially were believed the earliest pachycephalosaurians, both from China; but they have then been revealed being very archaic ceratopsians between ''Psittacosaurus'' and ''Yinlong''. Still mysterious is the identity of the poorly-known Early Cretaceous ''[[http://en.wikipedia.org/wiki/Stenopelix Stenopelix]]'', whose pelvis was found in Europe in the XIX century. Originally believed an hypsilophodont and then a pachycephalosaur, today is regarded as a basal ceratopsian.
36
37	----
38
39	'''Cousins in the South?:''' ''[[http://en.wikipedia.org/wiki/Serendipaceratops Serendipaceratops]]'' & ''[[http://en.wikipedia.org/wiki/Notoceratops Notoceratops]]''
40
41	* All confirmed ceratopsians have been found in the Northern Hemisphere, either in Asia - especially the earlier basal forms - or in North America (almost-all the [[UsefulNotes/PrehistoricLifeCeratopsids horned ones]]). The two animals here were believed the only two exceptions of the rule. ''Notoceratops'' ("southern horned face" indeed) was found in South America in year 1918, and traditionally believed a Late Cretaceous protoceratopsian which migrated in South America from North America (like some contemporary ornithopods, see [[UsefulNotes/StockDinosaursOrnithischianDinosaurs "Kritosaurus australis"]]). But its only remain, a piece of jaw, could be from an ornithopod instead. The Early Cretaceous ''Serendipaceratops'', on the other hand, was found in Australia in 2003 by the two palaeontologists that described ''Leaellynasaura'' in 1989. Initially, the discoverers had not considered that its only remain (a forearm bone) might have been ceratopsian, as at this would have been the last group of dinosaurs one would have expected to find in the LandDownUnder -- to the point they thought it was from a theropod. Some months later, however, another colleague pointed out the similarity to this bone of the more-known ''Leptoceratops'', and they decided to name it with the MeaningfulName ''Serendipaceratops''. However, the remain is too incomplete to confidently be placed in any known ornithischian group, and some think it was an ankylosaur like ''Minmi''.
42
43	----
44
45	[[/folder]]
46

Context UsefulNotes / PrehistoricLifeCeratopsidPredecessors