AVIS-IBIS

Birds of Indian Subcontinent

Redescription, palaeobiogeography and palaeoecology of Coniasaurus crassidens Owen, 1850 (Squamata) from the Lower Chalk (Cretaceous; Cenomanian) of SE England

Publication Type:Journal Article
Year of Publication:1999
Authors:CALDWELL, MICHAELW, COOPER, JOHNA
Journal:Zoological Journal of the Linnean Society
Volume:127
Issue:4
Date Published:1999
ISBN Number:1096-3642
Keywords:Corvidae, Corvus, Corvus corone, dolichosaurs, Europe, mosasaurs, palaeoecology -palaeobiogeography, squamates
Abstract:Type and referred specimens of Coniasaurus crassidens from the Lower Chalk (Upper Cretaceous; Cenomanian) of southeast England, are re-described. The type is a left maxilla associated with 14 dorsal vertebrae. The maxilla is elongate, bears a low ascending process, and has a long and posteriorly positioned external narial margin. The first maxillary tooth is pointed and bears a groove on the labial face; more posterior maxillary teeth are increasingly rounded and bulbous, and have a single groove on the labial face. Mandibles assigned to Coniasaurus cf. C. crassidens possess teeth of similar form; mandibular bones include the dentary, splenial, angular, coronoid, prearticular, and surangular. A number of features show important similarities to later mosasaurs and contemporaneous groups such as dolichosaurs. These new data provide a very different picture of coniasaurs and their mode of life in the early Upper Cretaceous. The functional morphology of coniasaur teeth is unique and shows occlusion between the lingual platforms of the upper teeth with the crowns of the lower teeth. Coniasaurs can be considered as analgous to small sauropterygians in terms of general morphology, habitats, and trophic structure. Coniasaur distributions in the Cenomanian and Turonian of Europe and North America are similar to the palaeobiogeographic patterns of other organisms living in the Tethys and SuperTethys Seaway.
URL:http://dx.doi.org/10.1111/j.1096-3642.1999.tb01380.x
Short Title:Zoological Journal of the Linnean Society
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith