Teiidae

Taxobox
name = Teiidae

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image_width = 200px
image_caption = "Tupinambis teguixin"
regnum = Animalia
phylum = Chordata
classis = Sauropsida
ordo = Squamata
familia = Teiidae
subdivision_ranks = Genera
subdivision = See text.

Teiidae is a family of lizards native to the New World, generally known as whiptails. The group includes the parthenogenic genera "Cnemidophorus" and "Aspidoscelis", and the non-parthenogenic "Tupinambis".

Morphology

Teiids can be distinguished from other lizards by the following characteristics: they have large rectangular scales that form distinct transverse rows ventrally and generally small granular scales dorsallycite book |editor=Cogger, H.G. & Zweifel, R.G.|author= Bauer, Aaron M.|year=1998|title=Encyclopedia of Reptiles and Amphibians|publisher= Academic Press|location=San Diego|pages= 170-171|isbn= 0-12-178560-2] , they have head scales that are separate from the skull bones, and the teiid teeth are solid at the base and "glued" to the jaw bones. Additionally, all teiids have a forked, snake like tongue. They all possess well-developed limbs.

Teiids are all terrestrial and diurnal, and are primarily carnivorous or insectivorous, although some will include a small amount of plant matter in their diet. They all lay eggs, with some species laying very large clutches.

Parthenogenesis

Certain species of whiptail lizards have all-female or nearly all-female populations. [AAAS – [http://www.sciencemag.org/cgi/content/abstract/135/3499/212 All-Female Species of the Lizard Genus Cnemidophorus, Teiidae] ] These lizards reproduce by parthenogenesis, and research has shown that simulated mating behavior increases fertility. For instance, one female lies on top of another, engaging in pseudocopulation. When they lay eggs, the lizard that was on bottom has larger eggs while the one on top has smaller. The lizards switch off this role each mating season. [Nerve.com – [http://www.nerve.com/Regulars/ScienceOfSex/09-19-00/09-19-00.asp The Science of Sex] . Simon LeVay, Ph.D.] The offspring are genetic clones of the mother, sparking debate as to how these lizards evolve or adapt to the environment. [American Museum of Natural History – [http://www.amnh.org/exhibitions/expeditions/treasure_fossil/Treasures/Unisexual_Whiptail_Lizards/lizards.html?50 Unisexual Whiptail Lizards] ]

Genera

Family: Teiidae
* Genus "Ameiva" - Jungle-runners (about 30 species)
* Genus "Aspidoscelis
* Genus "Callopistes" - False monitors (2 species)
* Genus "Cnemidophorus" - Whiptail lizards (about 60 species)
* Genus "Crocodilurus" - Crocodile Tegu (1 species)
* Genus "Dicrodon" - Desert tegus (3 species)
* Genus "Dracaena" - Caiman lizards (2 species)
* Genus "Kentropyx" - (9 species)
* Genus "Teius" - (3 species)
* Genus "Tupinambis" - Tegus (7 species)

References

*Pianka, E. R. and L. J. Vitt. 2003 "Lizards: Windows to the evolution of diversity". University of California Press. Berkeley.