Evans, Susan E. Department of Anatomy and Developmental Biology, University College London, London, United Kingdom.
Last reviewed:April 2020
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- Extant forms
- Anatomy of skull and jaws
- Early rhynchocephalians
- Related Primary Literature
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An order of lepidosaurian reptiles represented by one extant species, Sphenodon punctatus, commonly known as the tuatara. The reptilian members of the order Rhynchocephalia are referred to as the tuatara (also tuataras) [Fig. 1]. There is one surviving species of tuatara: Sphenodon punctatus. Previously, it was thought that there was a second extant species: Sphenodon guntheri. However, phylogenetic analyses have determined this former species to be a subspecies of Sphenodon punctatus. Thus, the two extant subspecies are known taxonomically as Sphenodon punctatus punctatus and Sphenodon punctatus guntheri. See also: Lepidosauria; Reptilia
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