Beishanlong is a genus of giant ornithomimosaurian theropod dinosaur from the Early Cretaceous of China. It is the second-largest ornithomimosaur discovered, only surpassed by the related Deinocheirus.
Discovery and naming
Three fossils of
Beishanlong were found in the early twenty-first century in Northwestern China at the
White Ghost Castle site, in the province of
Gansu. The
type species is
Beishanlong grandis, described and named online in 2009 by a team of Chinese and American paleontologists, and formally published in January 2010 by the same
Peter Makovicky,
Li Daiqing,
Gao Keqin,
Matthew Lewin,
Gregory Erickson and
Mark Norrell. The generic name combines a references to the
Bei Shan, the "North Mountains", with a Chinese
long, "dragon". The specific name means "large" in
Latin, in reference to the body size.
Beishanlong lived in the late Aptian stage,
Description
Beishanlong is of a considerable size, approximating the largest-known individuals of
Gallimimus, which have been estimated to reach eight metres. According to the description,
Beishanlong "is one of the largest definitive ornithomimosaurs yet described, though histological analysis shows that the holotype individual was still growing at its death." A
histology study of the bone structure of the
fibula found thirteen or fourteen growth lines, indicating the individual was subadult, though growth had already slowed.
The size of this subadult individual is estimated at in length and in body mass.
[Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 112]
The build of Beishanlong was rather robust. The arms and legs were long, though lacking the extremely elongated hands, feet and claws of later forms.
Classification
Beishanlong was by the describers assigned to the Ornithomimosauria, in a more basal position.
Beishanlong was closely related to fellow ornithomimosaurian
Harpymimus. Together they formed a
polytomy with the main ornithomimosaurian branch just below
Garudimimus.
In 2014 Yuong-Nam Lee
et al. recovered
Beishanlong as a member of
Deinocheiridae basal to a
clade containing
Garudimimus and
Deinocheirus.
[Yuong-Nam Lee, Rinchen Barsbold, Philip J. Currie, Yoshitsugu Kobayashi, Hang-Jae Lee, Pascal Godefroit, François Escuillié & Tsogtbaatar Chinzorig (2014) "Resolving the long-standing enigmas of a giant ornithomimosaur Deinocheirus mirificus". Nature (advance online publication) .]
See also
-
Timeline of ornithomimosaur research
External links
