Sinornithosaurus

Sinornithosaurus
Temporal range: Early Cretaceous (Barremian), 124.6–122 Ma
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S. millenii fossil, Hong Kong Science Museum
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: †Dromaeosauridae
Clade: †Microraptoria
Genus: †Sinornithosaurus
Xu, Wang & Wu, 1999
Type species
†Sinornithosaurus millenii
Xu, Wang, & Wu, 1999
Species
  • †S. millenii Xu, Wang, & Wu, 1999
  • †S. haoiana? Liu, Ji, Tang & Gao, 2004

Sinornithosaurus (derived from a combination of Latin and Greek, meaning 'Chinese bird-lizard') is a genus of feathered dromaeosaurid dinosaur from the early Cretaceous Period (late Barremian) of the Yixian Formation in what is now China.[1] It was the fifth non–avian feathered dinosaur genus discovered by 1999. The original specimen was collected from the Sihetun locality of western Liaoning. It was found in the Jianshangou beds of the Yixian Formation, dated to 124.5 million years ago. Additional specimens have been found in the younger Dawangzhangzi bed, dating to around 122 million years ago.[2]

Xu Xing described Sinornithosaurus and performed a phylogenetic analysis which demonstrated that it is basal, or primitive, among the dromaeosaurs.[3] He has also demonstrated that features of the skull and shoulder are very similar to Archaeopteryx and other avialans. Together these two facts demonstrate that the earliest dromaeosaurs were more like birds than the later dromaeosaurs were.

Sinornithosaurus was among the smallest dromaeosaurids, with the holotype measuring 1.2 metres (3.9 ft) long and weighing 3–5 kilograms (6.6–11.0 lb).[4][5]

  1. ^ Swisher, Carl C.; Wang, Yuan-qing; Wang, Xiao-lin; Xu, Xing; Wang, Yuan (1999). "Cretaceous age for the feathered dinosaurs of Liaoning, China" (PDF). Nature. 400 (6739): 58–61. Bibcode:1999Natur.400...58S. doi:10.1038/21872. S2CID 4424629.
  2. ^ Zhou, Z. (2006). "Evolutionary radiation of the Jehol Biota: chronological and ecological perspectives". Geological Journal. 41 (3–4): 377–393. doi:10.1002/gj.1045.
  3. ^ Xu, Xing; Wang, Xiao-Lin; Wu, Xiao-Chun (1999). "A dromaeosaurid dinosaur with a filamentous integument from the Yixian Formation of China". Nature. 401 (6750): 262–266. Bibcode:1999Natur.401..262X. doi:10.1038/45769. S2CID 4430574.
  4. ^ Paul, Gregory S. (2016). The Princeton Field Guide to Dinosaurs. Princeton University Press. p. 147. ISBN 978-1-78684-190-2. OCLC 985402380.
  5. ^ Xu, Xing; Qin, Zi-Chuan (2017). "A new tiny dromaeosaurid dinosaur from the Lower Cretaceous Jehol Group of western Liaoning and niche differentiation among the Jehol dromaeosaurids" (PDF). Vertebrata PalAsiatica. 55 (2): 129–144. S2CID 44178386.