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Full-Text Articles in Animal Sciences
A New Partial Skeleton Of A Cryptocleidoid Plesiosaur From The Upper Jurassic Sundance Formation Of Wyoming, Benjamin C. Wilhelm, F. Robin O’Keefe
A New Partial Skeleton Of A Cryptocleidoid Plesiosaur From The Upper Jurassic Sundance Formation Of Wyoming, Benjamin C. Wilhelm, F. Robin O’Keefe
Biological Sciences Faculty Research
Cryptocleidoid plesiosaurs from the Upper Jurassic are well known from the Oxford Clay (Callovian) of the United Kingdom. The plesiosaurs of the nearly coeval Sundance Formation (Oxfordian) of North America are poorly known, but are thought to include two cryptocleidoid taxa:Pantosaurus striatus and Tatenectes laramiensis. Here we present two specimens recently recovered from the Bighorn Basin of Wyoming. The first specimen comprises three articulated adult cervical vertebrae and fragments of a fourth. This specimen preserves a posteriorly directed cervical neural spine, a character diagnostic of Pantosaurus striatus. It also resembles Pantosaurus in the morphology of its cervical …
The Braincase Of Youngina Capensis (Reptilia, Diapsida): New Insights From High-Resolution Ct Scanning Of The Holotype, Nicholas M. Gardner, Casey M. Holliday, F. Robin O’Keefe
The Braincase Of Youngina Capensis (Reptilia, Diapsida): New Insights From High-Resolution Ct Scanning Of The Holotype, Nicholas M. Gardner, Casey M. Holliday, F. Robin O’Keefe
Biological Sciences Faculty Research
Detailed descriptions of braincase anatomy in early diapsid reptiles have been historically rare given the difficulty of accessing this deep portion of the skull, because of poor preservation of the fossils or the inability to remove the surrounding skull roof. Previous descriptions of the braincase of Youngina capensis, a derived stem-diapsid reptile from the Late Permian (250 MYA) of South Africa, have relied on only partially preserved fossils. High resolution X-ray computed tomography (HRXCT) scanning, a new advance in biomedical sciences, has allowed us to examine the reasonably complete braincase of the holotype specimen of Youngina capensis for the …
Evidence Of Pachyostosis In The Cryptocleidoid Plesiosaur Tatenectes Laramiensis From The Sundance Formation Of Wyoming, Hallie P. Street, F. Robin O’Keefe
Evidence Of Pachyostosis In The Cryptocleidoid Plesiosaur Tatenectes Laramiensis From The Sundance Formation Of Wyoming, Hallie P. Street, F. Robin O’Keefe
Biological Sciences Faculty Research
In this paper we present evidence for pachyostosis in the cryptocleidoid plesiosaur Tatenectes laramiensis Knight, 1900 (O'Keefe and Wahl, 2003a). Pachyostosis is not common in plesiosaurs and is particularly rare in non-pliosaurian plesiosaurs, although enlarged gastralia were first recognized in Tatenectes by Wahl (1999). This study aims to investigate the nature of the disproportionately large gastralia of Tatenectes m greater depth, based on new material. A recently discovered partial skeleton consisting of a dorsal vertebral series, ribs, gastralia, and a complete pelvic girdle was collected from the Jurassic-aged Sundance Formation of the Bighorn Basin in Wyoming during the summer of …