''Ankylosphenodon'' is an extinct species of

sphenodontian Rhynchocephalia (; ) is an order of lizard-like reptiles that includes only one living species, the tuatara (''Sphenodon punctatus'') of New Zealand. Despite its current lack of diversity, during the Mesozoic rhynchocephalians were a diverse g ...

known from Tepexi de Rodriguez,

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. It is known from Early Cretaceous

sedimentary Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

deposits from the Tlayua formation.

Lifestyle

''Ankylosphenodon'' is thought to have been an aquatic reptile due to its pachyostotic skeleton and other anatomical features often seen in aquatic animals. There is also evidence that its teeth were constantly growing throughout its lifetime, which may be indicative of

herbivory A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

, a rare characteristic among

Lepidosauria The Lepidosauria (, from Greek meaning ''scaled lizards'') is a subclass or superorder of reptiles, containing the orders Squamata and Rhynchocephalia. Squamata includes snakes, lizards, and amphisbaenians. Squamata contains over 9,000 species ...

References

Sphenodontia Cretaceous reptiles of North America Prehistoric reptile genera {{Cretaceous-reptile-stub