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Sinraptor dongi

Second drawing of the day...though the date has changed already. This is Sinraptor dongi an allosauroid from the Jurassic of Xinjiang, China. There are two recognised species of Sinraptor, S. dongi and S. hepingensis. S. hepingensis was initially described as the third species of Yangchuanosaurus after Y. shangyouensis and Y. magnus (Gao 1992 Vertebrata PalAsiatica 30: 313-324) but was subsequently assigned to the genus Sinraptor (Currie and Zhao 1993 Canadian Journal of Earth Sciences 30: 2037-2081). Compared to Yangchuanosaurus, Sinraptor has a relatively longer and lower skull. The two genera are united as Sinraptoridae. One of the distinchuishing features of sinraptorids is the high number (more than two) of accessory openings in the antorbital fossa. Another interesting feature of Sinraptor is the tall plate-like neural spines of the dorsal vertebrae. This is quite similar to Metriacanthosaurus such that Paul (1988 Predatory Dinosaurs of the World) synonymised Yangchuanosaurus with Metriacanthosaurus - he used M. shangyouensis instead of Y. shangyouensis.

I had two opportunities of studying the specimen of S. dongi at the IVPP. S. dongi is stored in an offsite warehouse about an hour's drive out from the IVPP. It is really a warehouse and mounted specimens of Sinraptor, Monolophosaurus, and a prosauropod (I forgot what it was) are just standing there amongst wooden crates and discarded packing materials, literally collecting dust. And it was damn cold...

Comments

Zach said…
I always wondered if the Sinraptoridae included more than just Sinraptor. Thanks for clearing that up, Manabu!
Mambo-Bob said…
No problem...Sinraptorids are one of my favourite groups of theropods. Personally I think their skulls look cool!
Zach said…
Yeah, they're like...streamlined allosaurs.

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