Phylogenetic relationships of leptellinid brachiopods

Abstract

The relationships among the diverse genera comprising the family Leptellinidae (Brachiopoda) are reviewed in the light of the revised edition of the Treatise on Invertebrate Palaeontology. Taxonomic work reassessed all the genera identified as Leptellinidae in the most current classification. Four genera were discarded, namely Bekkerella, Benignites, Leptastichidia and Nikitinamena. Cladistic analysis reveals the paraphyly of these genera; their abandonment leading to more morphologically coherent subdivisions of the family. Two subfamilies, Leptellininae and Palaeostrophomeninae, are emended and taxonomically restructured. The palaeogeographical history of the Leptellinidae is complicated. The Leptellinidae are first recorded in Baltica in the late Floian (Early Ordovician) and rapidly dispersed to circum-Iapetus palaeocontinents by the Dapingian, thence to most terranes composing Gondwana by the Darriwilian (Middle Ordovician).

Key words:

• Biogeography
• Brachiopoda
• cladistics
• Leptellinidae
• Ordovician
• Palaeozoic
• taxonomy

Acknowledgements

I gratefully acknowledge the SYNTHESYS grant (DK-TAF 4103). I thank Professor David Harper for facilitating my stay and research at the Geologisk Museum, Copenhagen, Denmark. Drs Ian Percival and Zhan Renbin are gratefully thanked for their constructive criticism of the manuscript that greatly enhanced its final version. I thank Stephen McLoughlin for his editorial input. I thank Gail (British Geological Survey Library, Edinburgh, Scotland) for providing vital research articles.