New trigonioid bivalves from the Early Jurassic to earliest Cretaceous of the Antarctic Peninsula region: systematics and austral paleobiogeography

New discoveries of trigonioid bivalves are documented from three areas in the Antartic Peninsula: the Fossil Bluff Group of Alexander Island, the Latady Formation of the Orville Coast, and the Byers Group of Livingston Island, South Shetland Islands. Eleven taxa are described, representing six gener...

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Bibliographic Details
Published in:Journal of Paleontology
Main Author: Kelly, Simon R. A.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1995
Subjects:
Online Access:http://dx.doi.org/10.1017/s0022336000026925
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000026925
Description
Summary:New discoveries of trigonioid bivalves are documented from three areas in the Antartic Peninsula: the Fossil Bluff Group of Alexander Island, the Latady Formation of the Orville Coast, and the Byers Group of Livingston Island, South Shetland Islands. Eleven taxa are described, representing six genera or subgenera. The faunas are characterized by genera including Vaugonia ( Vaugonia ), the first Early Jurassic trigonioid recognized on the continent; Vaugonia ( V .) and V. ( Orthotrigonia ?) in the Late Jurassic; and Iotrigonia ( Iotrigonia ), Myophorella ( Scaphogonia ), and Pterotrigonia ( Pterotrigonia ), which span the Jurassic–Cretaceous boundary, reaching the Berriasian stage. The following species are new: Pterotrigonia ( P .) cramei n. sp., Pterotrigonia ( P. ) thomsoni n. sp., Vaugonia ( V. ) orvillensis n. sp., and V. ( Orthotrigonia ?) quiltyi n. sp. The faunas show affinities with those of New Zealand and southern Africa. Trigonioids characterize the shallower marine biofacies in the Jurassic of the Antarctic and reflect the principal shallowing events in the history of the region.