Phylogeny of Middle–Late Ordovician lituitid cephalopods based on cladistic analysis

Abstract

Phylogenetic studies are rare in early Palaeozoic cephalopods. Here, we present the first cladistic analysis of the order Lituitida based on published, as well as some new, material. Three clades are recovered within the ingroup of lituitids, Sinoceras, Ancistroceras and Lituites; the former two groups correspond to the family Sinoceratidae, and the latter one to the Lituitidae. The topology shows that the Sinoceratidae represents the basal branch, while the Lituitidae represents a monophyletic, derived clade. Furthermore, we describe new material of four species (three of which are newly defined) in four genera of the order Lituitida from the well-exposed, Middle to Upper Ordovician of Hubei (South China). The described species include Lituites evolutus Fang, Chen & Zhang, Sinoceras complexum Fang sp. nov., Tyrioceras longicameratum Fang sp. nov. and Rhynchorthoceras yizanense Fang sp. nov. Tyrioceras longicameratum from South China is the first reported occurrence of Tyrioceras in China, which has significant palaeogeographical implications.

http://zoobank.org/urn:lsid:zoobank.org:pub:470C958E-26DD-4A2E-B0FC-4B2B178367FE

Keywords:

• cladistic analysis
• maximum parsimony
• Lituitidae
• Sinoceratidae
• Lituitida
• Middle–Late Ordovician

Acknowledgements

We are indebted to David Evans, Tim Ewin and an anonymous reviewer for their helpful constructive suggestions. This work was supported by the Chinese Academy of Sciences (grant number XDB26000000), National Natural Science Foundation of China (grant numbers 42002009, 42030510), State Key Laboratory of Palaeobiology and Stratigraphy (grant number 20192102), and Administrative Committee of Zhangjiajie UNESCO Global Geopark (No. 202001) to Xiang Fang and Yuandong Zhang. Martina Aubrechtová acknowledges support from Research Plan of the Institute of Geology of the Czech Academy of Sciences (RVO67985831), and Faculty of Science, Charles University (SVV 244-2604372 and UNCE/SCI/006). This is a contribution to the IGCP projects 653 (The Onset of the Great Ordovician Biodiversification Event) and 735 (Rocks and the Rise of Ordovician Life).

Supplemental material

Supplemental material for this article can be accessed at: http://doi.org/10.1080/14772019.2021.1944354

 

Associate Editor: Tim Ewin