Elmisaurus
Live reconstruction of Elmisaurus
- Elmisaurus rarus
- (?) Elmisaurus elegans ( Parks, 1933)
Elmisaurus was a theropod dinosaur from the group of Oviraptorosauria, who lived in the Upper Cretaceous of Asia and possibly North America.
The classification of these little-known genus within the Oviraptorosauria is controversial. While some researchers Elmisaurus expected to Caenagnathiden, assign it to another creating a family, the Elmisauridae to.
From Elmisaurus two types have been described: Elmisaurus rarus from Mongolia and Elmisaurus elegans from Alberta and Montana, Elmisaurus elegans is often seen as synonymous with Chirostenotes.
History of Research
The type species Elmisaurus rarus was discovered in 1970 and first described in 1981 by Halszka Osmólska. The type is based on hand and foot bones, which were found in Ömnö Gobi Aimag, a Aimag of Mongolia. Stratigraphically the fossils of about 70 million year old sediments originate (early Maastrichtian ) of Nemegt lineup. The name Elmisaurus is derived from the Mongolian ölmyi ( "foot" ) and the Ancient Greek sauros ( " lizard" ), which shall indicate the ossification of the metatarsals, an autapomorphy ( distinguishing characteristic ) of Elmisaurus.
As 1989, Currie fossils from the Dinosaur Park Formation of Alberta (Canada) as another way Elmisaurus elegans. The type material of this species was originally described by Parks (1933 ) as a new type of Ornithomimus - Ornithomimus elegans - although Sternberg a year later found that it was not a Ornithomimide. Later keep Currie and Russell (1988 ) the elegans species to be identical with Chirostenotes pergracilis, although these researchers point out that she was graceful and perhaps could be managed as separate Chirostenotes - style - as Chirostenotes elegans. 1989 Currie described two new finds, which he attributed to the elegans species of the genus Elmisaurus. Some later studies, including Osmólska et al. (2004), however, reject this assignment and keep the elegans type still kind of Chirostenotes.
Currie and Russell ( 1988) suggest that Caenagnathus Sternbergi with Elmisaurus (or Chirostenotes ) elegans is identical. The type species of Caenagnathus, Caenagnathus collinsi, keep these researchers for identical pergracilis with Chirostenotes. This allocation is shared by many later authors, such as Osmólska et al. (2004 ), where Caenagnathus is usually considered invalid.
More recently, some Fußknochenfunde were attributed from the Hell Creek Formation of Montana Elmisaurus elegans ( Varricchio, 2001; Buckley, 2002). The metatarsal bone described by Buckley are unusually large - three times as large as the findings described by Varricchio.