Heterochronic growth of ostracods (Crustacea) from microbial deposits in the aftermath of the end-Permian extinction

Abstract

The Kokarkuyu Formation (Early Triassic) from the Çürük Dağ section, Western Taurus, Antalya Nappes, Turkey was carefully sampled for a taxonomic study of the ostracods. A total of 57 species belonging to 15 genera are recognized. Three species are newly described: Monoceratina hussonae sp. nov., Reviya sylvieae sp. nov. and Eukloedenella adcapitisdolorella sp. nov. The present data are the first Neo-Tethyan illustration of ostracod survival in the aftermath of the end-Permian extinction in a refuge of microbial origin. Ostracods are abundant within the microbialites at the base of the formation and allow the reconstruction of ontogenetic series for nine species. Shape variations through ontogeny are described for seven species: Bairdia? kemerensis, Praezabythocypris? ottomanensis, Liuzhinia antalyaensis, Paracypris gaetanii, Reviya curukensis, R. sylvieae and Eukloedenella adcapitisdolorella. Paedomorphosis through deceleration and peramorphosis through acceleration are identified as secondary survival strategies following the end-Permian extinction.

http://zoobank.org/urn:lsid:zoobank.org:pub:6849AB0D-B085-47BE-950A-BC98CC50C4E3

Keywords:

• Crustacea
• ostracods
• Early Triassic
• microbialites
• heterochrony
• Çürük Dağ

Acknowledgements

This work is part of IGCP 572 ‘Restoration of marine ecosystems following the Permian–Triassic mass extinction: lessons for the present’ and Chinese programs NSFC (40621002) and 111 (B08030) and was funded by Actions transversales du museum (ATM) Biodiversités actuelles et fossiles. It was undertaken at the UMR 7207 Centre de recherche sur la paléobiodiversité et les paléoenvironnements (CR2P), Paris. I thank Prof. Dave Horne (University College, London, UK), Dr Gengo Tanaka (Japan Agency for Marine-Earth Science and Technology, Japan) and an anonymous reviewer for their comments and corrections that greatly improved an earlier version of the manuscript. I am also grateful to Prof. Horne for his valuable advice. My gratitude is addressed to Dr Sylvie Crasquin (CNRS, Pierre et Marie Curie University, Paris, France) for her advice, trust, and motherly support; it will always be remembered. I am indebted to Prof. Steve Kershaw (Brunel University, UK) and Dr Pierre-Yves Collin (Burgundy University, France) for their constructive remarks, and to Aymon Baud (Lausanne, Switzerland) and Erdal Kosun (Akdeniz University, Antalya, Turkey) for their help in the field. I thank Martine Fordant and Alexandre Lethiers (Pierre et Marie Curie University), respectively, for their help with the processing of samples and the drawings. Finally I thank Brigitte Létang (France) for patiently correcting my ‘frenglish’.