A new Ordovician (Katian) calymenid, Gravicalymene bakeri sp. nov., from the Gordon Group, Tasmania, Australia

Abstract

A previously unreported calymenid trilobite, Gravicalymene bakeri sp. nov., is described herein from Late Ordovician (latest Eastonian, Katian) shales of the Gordon Group, Tasmania. This is the first record of Gravicalymene from the Ordovician of East Gondwana (Australasia), a genus which is otherwise relatively well-known from Avalonia, Baltica and Laurentia (i.e., Europe and North America). The current taxonomic status of the genus Gravicalymene and other morphologically similar genera (e.g., Apocalymene, Calymene, Flexicalymene, and Sthenarocalymene) is also discussed.

P.M. Smith [[email protected]] Palaeontology Department, Australian Museum Research Institute, Sydney, New South Wales, 2010, Australia and, Department of Biological Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia; M.C. Ebach [[email protected]] Palaeontology, Geobiology and Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, Australia.

Keywords:

• East Gondwana
• Late Ordovician
• Eastonian
• trilobite
• Calymeninae
• Sthenarocalymene

Acknowledgements

We thank David Holloway of Museums Victoria, Melbourne for discussions on calymenid taxonomy; John Laurie of Geoscience Australia and Macquarie University for discussions on Tasmanian Cambro-Ordovician Stratigraphy; Scott Morrison of the University of Oregon for supplying digital versions of older references that were difficult to obtain; Matthew McCurry of the Australian Museum, Sydney for generously allowing access to the specimens under his care, and kindly allowing PMS to use the camera set-up in the museum’s palaeobiology laboratory. We are grateful to Editor B. Kear, Associate Editor T. Topper, Per Ahlberg and two anonymous reviewers for their constructive reviews of the manuscript, which greatly improved its quality.

Disclosure statement

No potential conflict of interest was reported by the author(s).