Oldest meiolaniid turtle remains from Australia: evidence from the Eocene Kerosene Creek Member of the Rundle Formation, Queensland

Fossil meiolaniid turtles are known only from South America and Australasia. The South American record is restricted to the Eocene, and comprises two genera: Niolamia and Gaffneylania. The Australasian meiolaniid record is more diverse, with three genera known (Ninjemys, Warkalania and Meiolania); h...

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Bibliographic Details
Published in:Alcheringa: An Australasian Journal of Palaeontology
Main Authors: Poropat, Stephen F., Kool, Lesley, Vickers-Rich, Patricia, Rich, Thomas H.
Other Authors: Swinburne University of Technology
Format: Article in Journal/Newspaper
Language:unknown
Published: Taylor & Francis 2016
Subjects:
Online Access:http://hdl.handle.net/1959.3/435222
https://doi.org/10.1080/03115518.2016.1224441
Description
Summary:Fossil meiolaniid turtles are known only from South America and Australasia. The South American record is restricted to the Eocene, and comprises two genera: Niolamia and Gaffneylania. The Australasian meiolaniid record is more diverse, with three genera known (Ninjemys, Warkalania and Meiolania); however, the oldest known specimens from this continent are significantly younger than those from South America, deriving from upper Oligocene sediments in South Australia and Queensland. Herein, we describe the oldest meiolaniid remains found in Australasia to date. The specimens comprise a posterior peripheral, a caudal ring, and an osteoderm, all of which derive from the middle–upper Eocene Rundle Formation of The Narrows Graben, Gladstone, eastern Queensland. Despite their fragmentary nature, each of these specimens can be assigned to Meiolaniidae with a high level of confidence. This is particularly true of the partial caudal ring, which is strongly similar to those of Niolamia, Ninjemys and Meiolania. The extension of the Australasian meiolaniid record to the Eocene lends strong support to the hypothesis that these turtles arose before South America and Australia detached from Antarctica, and that they were consequently able to spread across all three continents.