REPTILIA: SQUAMATA: XENOSAURIDAE: Xenosaurus

Xenosaurus grandis (Gray, 1856)

Mexican Bark Lizard

Text & photos by Robert Sprackland.

Range: Southern Mexico, at higher altitudes in mountain forests.

Diagnosis: Head triangular, broad posteriorly; body squat with numerous small tubercles; tail very thin, slightly longer than snout-vent length. There is no external ear opening, nor are eyelids present.

Description:

Natural History: Xenosaurs live near arid regions but generally stay in forests or well-planted areas where humidity and rainfall are common. They climb well, but are also found in rocky crevices. This species is insectivorous, but also takes some plant matter (flowers and fruits) and the rare small vertebrate.

Reproduction: Xenosaurs bear 1 (usually) to 3 (very rarely) live young that measure about 2.25 inches in length.

Taxonomy & Relationships:  “Xenosaurus” is Greek for “strange lizard,” probably referring to the difficulty it presented in determining its relationships with other lizards. The genus is now well supported as belonging to the Diploglossan group of the Anguimorpha.

Holotype: BMNH

Literature:

Barrows, Shirley and Hobart Smith. 1947. The skeleton of Xenosaurus grandis (Gray). University of Kansas Science Bulletin 31 part II (12): 227-281.

Fritts, Thomas. 1966. Notes on the reproduction of Xenosaurus grandis (Squamata: Xenosauridae). Copeia 1966(3): 598.

King, Wayne and Fred Thompson. 1968. A review of the American lizards of the genus Xenosaurus Peters. Bulletin of the Florida State Museum 12(2): 93-123.