Chirostenotes

Skeletal reconstruction of Chirostenotes

• Alberta (Canada)

• Chirostenotes pergracillis
• Chirostenotes elegans

Chirostenotes (from gr " small hand " ) is a genus theropod dinosaur from the Upper Cretaceous of North America. Chirostenotes one of the Caenagnathidae, a taxon within the Oviraptorosauria.

The late from the Campanian and early Masstrichtium derived fossils of the type species Chirostenotes pergracillis were discovered in the Dinosaur Park Formation in Alberta, a major Canadian reference from the Campanian. In addition to C. pergracillis another style is distinguished, C. elegans, which could be identical with the closely related Elmisaurus however. A large skeleton from the Horseshoe Canyon Formation C. pergracillis was attributed to this could be, however, also be a separate species.

Features

Chirostenotes was about 2.9 meters long, bipedal theropod. Much like some primitive Oviraptorosauria as Caudipteryx and Protarchaeopteryx could also Chirostenotes springs have worn. The long, slender jaws were toothless. Like some other Oviraptorosauria features of the skull of Chirostenotes by a large skull crest of which resembles that of modern cassowary. The foot is a Arctometatarsal - the second and fourth metatarsal bones in contact at the upper end and the third pressed back so that viewed from the front was visible only at the lower end of the metatarsus. This feature distinguishes the group of Arctometatarsalia but which is today no longer recognized. The metatarsal of Chirostenotes were long and represented 22 % of the length of the hind legs ( without toe ) out. Little is known about the diet of this animal, maybe it was an omnivorous or herbivorous.

Discovery history

In 1924, a pair of incomplete hands was discovered and described by Gilmore as Chirostenotes ( " small hand "). In 1932, the feet have been discovered and described by Charles M. Sternberg as Macrophalangia ( "big toe "). Although you could assign both finds the theropod later, it was unclear whether it is the same way. 1936, the jaw of the animal was discovered and later as Caenagnathus ( " new pine " ) described ( Sternberg, 1940), initially he was considered a bird jaw. The Caenagnathidae family, in which Chirostenotes is classified, still bears the name of this genus. 1988 a skeleton was discovered in a museum collection and examined, which was found in 1923 - this skeleton shows that all finds belong to the same dinosaur species. Since then, the finds are performed under the name Chirostenotes, as this name was given as the first (priority rule). Furthermore, were Chirostenotes pine attributed with strong teeth that are out today but as Ricardoestesia.