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Pterosauria of the Great Oolite Group (Bathonian, Middle Jurassic) of Oxfordshire and Gloucestershire, England

100%
O’Sullivan M., Martill D. M.
Acta Palaeontologica Polonica
|
2018
|
tom 63
|
nr 4
The current understanding of UK Middle Jurassic pterosaur taxonomy is under-developed, leading to it being previously considered a time of low diversity. This is despite the presence of a productive but under-studied pterosaur-bearing horizon extending over parts of Oxfordshire and Gloucestershire. This unit, informally called the Stonesfield Slate, is part of the Great Oolite Group and it produces the largest number of Middle Jurassic pterosaurs. There are over 200 specimens distributed across museums in the United Kingdom, America, and Australia, almost all of which are accessioned under the genus Rhamphocephalus and referred to three species: the type species Rhamphocephalus prestwichi, Rhamphocephalus bucklandi, and Rhamphocephalus depressirostris. This study reviews the British Middle Jurassic Pterosauria assemblage, evaluating both their systematics and taxonomic diversity. The holotype of Rhamphocephalus, an isolated skull table, is found to be a misidentified crocodylomorph skull and the genus is considered a nomen dubium. The holotype of Rhamphocephalus bucklandi is identified as missing and that of Rhamphocephalus depressirostris has characters diagnostic at a family level, not a generic or specific one. Both species are considered dubious. Detailed examination of the entire assemblage shows that rather than being monogeneric, the assemblage contains at least five pterosaur taxa, representing three families. This diversity includes the potential earliest occurrences of both Monofenestrata and Pterodactyloidea. A new genus, Klobiodon rochei gen. et sp. nov. is described based on a well-preserved mandible. The English Bathonian pterosaur assemblage is shown to be diverse and indicates that, as has been suggested in other studies, the low-diversity signal in the Middle Jurassic is at least partially artificial.
2
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A new monofenestratan pterosaur from the Kimmeridge Clay Formation (Kimmeridgian, Upper Jurassic) of Dorset, England

100%
Martill D. M., Etches S.
Acta Palaeontologica Polonica
|
2013
|
tom 58
|
nr 2
A specimen of slender skulled monofenestratan pterosaur from the Upper Jurassic Kimmeridge Clay Formation of Dorset, UK, is referred to the new genus and species Cuspicephalus scarfi. The dentition and posterior skull morphology suggest affinities with Darwinopterus, but a close relationship cannot be proved. There are also some similarities with the pterodactyloid Germanodactylus cristatus, but the presence of teeth on the distal rostrum excludes it from that genus. Pterosaur remains are rare in the Upper Jurassic of the UK and this specimen represents the first significant cranial remains of a pterosaur from the Kimmeridge Clay Formation, and possibly the first non−pterodactyloid monofenestratan outside China.
3
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Evolution of the pterosaur pelvis

80%
Hyder E. S., Witton M. P., Martill D. M.
Acta Palaeontologica Polonica
|
2014
|
tom 59
|
nr 1
Pterosaur pelvic girdles are complex structures that offer a wealth of phylogenetic and biomechanical information, but have been largely overlooked by pterosaur anatomists. Here, we review pterosaur pelvic morphology and find significant differences that correlate well with pterosaur clades identified in some phylogenetic analyses. We find that the length and orientation of the iliac processes, position of the acetabulum, extent of the ischiopubic plate and presence of supraneural fusion in adult individuals are taxonomically informative. Ontogenetic changes in pelvic morphology dictate that osteologically mature specimens are required to assess the development of many of these characteristics. We suggest that pelvic characters can readily be incorporated into pterosaur phylogenetic analyses and may assist in resolving the controversial interrelationships of this group. Distinctive pterosaur pelvic morphotypes suggest considerable differences in stance, locomotory kinematics and hindlimb functionality across the group.
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