Two new cowries (Gastropoda: Cypraeidae) from the middle Miocene of South Australia

Abstract

Yates, A.M., December, 2008. Two new cowries (Gastropoda: Cypraeidae) from the middle Miocene of South Australia. Alcheringa 32, 353–364. ISSN 0311-5518.

The South Australian specimens of the cypraeids Umbilia leptorhyncha (McCoy, 1877) and Lyncina (Austrocypraea) contusa (McCoy, 1877) are re-examined. Umbilia caepa sp. nov. differs from U. leptorhyncha in its smaller size, more strongly pyriform shape, weaker and less extensive apertural dentition, plate-like columellar margin of the posterior canal and more extensive basal flanges. True U. leptorhyncha is also recorded from the Cadell Formation of South Australia, demonstrating that the two species were sympatric in the Murray Basin. The specimens originally referred to Cypraea contusa var. from the Cadell Formation have had a confusing taxonomic history and they are here named as a new species Lyncina (Austrocypraea) cadella sp. nov. The new species differs from true L. (A.) contusa in its smaller size, less extensive malleations of the dorsal surface, fewer apertural teeth and a projecting internal margin of the fossula. These two new species boost a small but growing list of species that were endemic to the Murray Basin during the middle Miocene.

Key words:

• Cypraeidae
• Miocene
• Murray Basin
• Cadell Formation
• Umbilia
• Lyncina (Austrocypraea)

Acknowledgements

I wish to thank my parents for their assistance during innumerable collecting trips to the Cadell Formation during which the specimens described here were collected. I also thank Rolf Schmidt (Museum Victoria), Ben McHenry, and Dennis Rice (South Australian Museum) for assistance and allowing access to collections in their care. I thank Jonathan Todd for providing photographs of the holotype of Austrocypraea subcontusa. I thank Thomas Darragh and Lindsey Groves for their helpful reviews of the manuscript. Travel between South Africa and Australia was funded by Research Incentive money from the NRF to the School of Geoscience, University of the Witwatersrand.