Teiidae

lizard family

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Last updated

July 16, 2026

Quick Summary

The Teiidae family consists of mostly tropical American lizards, commonly known as tegus or whiptails. These lizards are characterized by their flat, elongated, forked tongues, which they use with Jacobson's organ to detect chemical cues.1234

Teiids are found in a variety of habitats, from rainforests to savannas. While some species, like the racerunners and whiptails, are found in the United States, the family is most diverse in Central and South America. Many species are carnivorous and can grow quite large, with some tegus reaching over a meter in length. Some teiids have been exploited for their leather, while others are popular in the pet trade.4153

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lizard
Annotated classification
Family Teiidae (racerunners, whiptails, and tegus) Osteoderms absent, supratemporal fossa open. Late Cretaceous to present. New World only, primarily in tropics and subtropics. Great variation in the family, including large terrestrial predators (Tupinambis), large semiaquatic snail eaters (Dracaena), and lacertid-like “racerunners” (Cnemidophorus).
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Family Teiidae (racerunners, whiptails, and tegus) Osteoderms absent, supratemporal fossa open. Late Cretaceous to present. New World only, primarily in tropics and subtropics. Great variation in the family, including large terrestrial predators (Tupinambis), large semiaquatic snail eaters (Dracaena), and lacertid-like “racerunners” (Cnemidophorus).
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reptile
Central and South America
The lizard family Teiidae, though represented in the United States by the racerunners and whiptails of the genus Cnemidophorus, is primarily tropical, and its area of greatest biological diversity begins in Central America with the large, conspicuous, and active ameivas (Ameiva). The Gymnophthalmidae (or microteiids), close relatives of…
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The lizard family Teiidae, though represented in the United States by the racerunners and whiptails of the genus Cnemidophorus, is primarily tropical, and its area of greatest biological diversity begins in Central America with the large, conspicuous, and active ameivas (Ameiva). The Gymnophthalmidae (or microteiids), close relatives of…
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