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.