Reptiles Database

Order Squamata
Suborder Anguinomorpha

Family Xenosauridae and Shinisauridae


Xenosaurus platyceps
© Wayne van Devender

The Xenosauridae consist of the Central American genus Xenosaurus and of two fossil North American genera, Exostinus and Restes, which are very close to Xenosaurus.

The status of the Chinese genus Shinisaurus is not completely clear. Macey et al. (1999) recently suggested to split the Xenosauridae into two separate families, the Sinisauridae and Xenosauridae, because of DNA sequence differences. Xenosaurids are rock-dwelling lizards. All species are diurnal and viviparous. Shinisaurus is special in that it is semi-aquatic and is known to feed on tadpoles and fish.

Zoological definition: The temporal arches are strongly developed, and the temporal openings are large and not roofed by skull bones. The bones of the skull are roughened by the fusion to them of the cranial osteoderms (Goin et al. 1978).

Cranial features:

  • Cephalic scales relatively small,
  • Cephalic osteodermal crust divided into conical mounds;
  • Frontals constricted between orbits;
  • Rectangular cross-section of skull owing to presence of canthal crest on temporal arch;
  • Widened and sculptured postorbital branch of jugal;
  • Jugal-squamosal contact on temporal arch;
  • Ectopterygoid exposed laterally on skull;
  • Carotid fossa reduced (after Borsuk-Bialynicka, 1986).

List of genera:

Subfamily Shinisaurinae

Subfamily Xenosaurinae

References:

Borsuk-Bialynicka,M. (1986)
On the diagnosis of the Xenosauridae (Anguimorpha)
in: Rocek,Z. (ed.), Studies in Herpetology, pp. 213-217
Charles University, Prague

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

Macey,J.R. et al. (1999)
Molecular phylognetics, tRNA evolution, and historical biogeoraphy in anguid lizards and related taxonomic families.
Mol. Phylogen. Evol. 12 (3) 250-272

Scherpner,Ch. in:
Klemmer,K., Wermuth,H. & Hediger,H., eds. (1979-1993)
Grzimeks Tierleben, Bd. 6: Kriechtiere
Deutscher Taschenbuch Verlag
p. 319-320

Zug,G.R.; Vitt, L.J. & Caldwell, J.P. (2001)
Herpetology, 2nd ed.
Academic Press San Diego, London, [...]XIV + 630 pp.