Cranial osteology, taxonomic reassessment, and phylogenetic relationships of the Early Cretaceous (Aptian-Albian) turtle Trinitichelys hiatti (Paracryptodira)

PeerJ. 2022 Nov 2:10:e14138. doi: 10.7717/peerj.14138. eCollection 2022.

Abstract

We describe the skull of the Early Cretaceous (Aptian-Albian) baenid turtle Trinitichelys hiatti using micro-computed tomography to provide new insights into the cranial anatomy of basal baenids and into the evolution of paracryptodires. We show that the validity of Trinitichelys hiatti vs Arundelemys dardeni still holds true, that the most basal known baenids for which skull material is known share an intriguing combination of features that are typical of either Pleurosternidae or Baenidae, and that the carotid system of Trinitichelys hiatti is intermediate to that of pleurosternids and more advanced baenids. Our expanded phylogenetic analysis confirms the traditional placement of Arundelemys dardeni, Lakotemys australodakotensis, and Trinitichelys hiatti as basal baenids, retrieves Helochelydridae along the stem of Baenoidea, but recovers Dinochelys whitei, Glyptops ornatus, Dorsetochelys typocardium, and Uluops uluops as basal branching Paracryptodira.

Keywords: Anatomy; Baenidae; Paracryptodira; Phylogeny; Systematics; Testudinata; Turtles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Fossils
  • Osteology
  • Phylogeny
  • Skull / diagnostic imaging
  • Turtles* / anatomy & histology
  • X-Ray Microtomography

Grants and funding

Yann Rollot, Serjoscha Evers, and Walter Joyce received funding from the Swiss National Science Foundation via project (SNF 200021_178780/1). There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.