Utahdactylus
From Wikipedia, the free encyclopedia
Utahdactylus Fossil range: Late Jurassic |
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Binomial name | ||||||||||
Utahdactylus kateae Czerkas and Mickelson, 2002 |
Utahdactylus (meaning "Utah finger") was a genus of extinct reptile from the Kimmeridgian-Tithonian-age Upper Jurassic Morrison Formation of Utah, USA. Based on DM 002/CEUM 32588 (an incomplete skeleton described as including a fragment of the skull, cervical, back, and caudal vertebrae, ribs, a scapulacoracoid, and limb bones), Czerkas and Mickelson (2002) identified as a rhamphorhynchoid pterosaur. Bennett (2007) concluded that it has no diagnostic features of the pterosauria, and cannot be positively identified beyond being an indeterminate diapsid.
[edit] History
The specimen was first described by Stephen Czerkas and Debra Mickelson as a pterosaur, with a long tail and an estimated wingspan of 1.20 meters (3.94 feet). The authors considered it to be a rhamphorhynchoid, due to its long tail and large but not elongate cervical vertebrae, but without the typical groove in its forelimb bones.[1] It was regarded as a rhamphorhynchoid based on an unprepared specimen in the most recent review of Morrison pterosaurs.[2]
In 2007, pterosaur specialist Chris Bennett published a redescription wherein he disagreed with Czerkas' and Mickelson's conclusions. He found several of the bone identifications and interpretations to be mistaken, such as the skull bone (interpreted here as just a bone fragment of unknown origin), elongate tail vertebra (rib), humerus (unknown), and the orientation of the bone described as a scapulacoracoid. He could not locate other bones seen as impressions, and found no evidence to suggest that the identifiable bones came from a pterosaur. In fact, he found the quality of the bones to differ from pterosaur bones. He concluded by identifying it as Diapsida incertae sedis, and a dubious name.[3]
[edit] References
- ^ Czerkas, Stephen A.; and Mickelson, Debra L. (2002). "The first occurrence of skeletal pterosaur remains in Utah", in Czerkas, Sylvia J. (ed.): Feathered Dinosaurs and the Origin of Flight. Blanding, Utah: The Dinosaur Museum, 3-13. ISBN 1-93207-501-1.
- ^ King, Lorin R.; Foster, John R.; and Scheetz, Rodney D. (2006). "New pterosaur specimens from the Morrison Formation and a summary of the Late Jurassic pterosaur record of the Rocky Mountain region", in Foster, John R.; and Lucas, Spencer G. (eds.): Paleontology and Geology of the Upper Morrison Formation, New Mexico Museum of Natural History and Science Bulletin, 36. Albuquerque, New Mexico: New Mexico Museum of Natural History and Science, 149-161.
- ^ Bennett, S. Christopher (2007). "Reassessment of Utahdactylus from the Jurassic Morrison Formation of Utah". Journal of Vertebrate Paleontology 27 (1): 257–260. doi: .
[edit] External links
- Utahdactylus in The Pterosaur Database
- Utahdactylus in The Pterosauria