Ichnologic note: in defence of Thatchtelithichnus Zonneveld, Bartels, Gunnell and McHugh, 2015

Abstract

The validity of the monotypic ichnogenus Thatchtelithichnus has been called into question due to an inference that it is a bioclaustration. Close analysis of the Thatchtelithichnus holmani holotype reveals that no part of this ichnotaxon involves a bioclaustration, and thus it remains a valid ichnotaxon. Thatchtelithichnus holmani has been observed on the bottom shell (plastron) of cryptodiran and pleurodiran turtles in North America and Egypt where it is interpreted to represent an attachment trace of aquatic ectoparasites. It has also been observed on dinosaur long bones where it may represent the activity of beetle larvae.

Keywords:

• Thatchtelithichnus
• Karethraichnus
• boring
• turtle bone
• bioclaustration

Acknowledgements

We thank our late colleagues Richard Bromley, Gregg Gunnell, Al Holman and George Pemberton for their advice on palaeontology, chelonian osteology, ichnology and borings in bones and shells. We are also grateful to Murray Gingras, Jon Bloch, and Michael Frick for discussions on ichnology, paleontology, aquatic turtle ecology and the distribution of parasites in modern turtle populations. We thank Journal editors Murray Gingras and Luis Buatois and two anonymous reviewers for their work in helping to improve this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.