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| Neotropical Runner, Ameiva ameiva (Linnaeus, 1758). Photographed in Grenada. This widespread species complex uses open areas in forests, but will also use a variety of man made habitats such as lawns. The populations of this animal on Tobago, Grenada, the Grenadines, and St. Vincent has been called Ameiva ameiva tobagana Cope, 1862. This bright blue individual is a male. |
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| Common Jungle Runner, Ameiva festiva (Lichtenstein and von Martens, 1856). Photographed in northeast Costa Rica. This is primarily a Central American species that also ranges into western Colombia. It uses forests and plantations and is abundant at many localities. They bask along streams and in open patches of forest to raise their body temperature. Food includes arthropods, frogs, and other lizards. Females 3 or 4 clutches of 1-4 eggs per annum. Adults reach 345 mm in total length. |
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| Four lined Jungle Runner, Ameiva quadrilineata (Hallowell, 1861). Photographed in northeastern Costa Rica. Hallowell's Ameiva ranges from Nicaragua to Panama. Probably most abundant in forests with an open canopy, including plantations. Arthropods are the primary food, but a population living on a beach ate amphipods. Adults reach 283 mm in total length. These are relatively short lived lizards, with females rarely surviving more than two breeding seasons. |
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| Burt's Whiptail Lizard, Aspidoscelis burti, Taylor, 1938. Photograph of a captive from Arizona. The species ranges from Arizona and New Mexico southward into Sonora, Mexico. Adult reach a body length of 140 mm, and a total length of 510 mm. As its names suggests it often occurs in canyons, along streambeds with sycamore and cottonwood trees. Females usually produces clutches of 3-5 eggs, but as many as 10 eggs have been reported. This lizard is extremely wary, and poorly known. This lizard was formerly placed in the genus Cnemidophorus. |
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| The Beach Racerunner, Cnemidophorus lemniscatus (Linnaeus, 1758). Photographed on Trinidad's east coast. Adults reach 330 mm in total length. It is distributed from the coastal lowlands of Central America to northern South America and the Amazon Basin, it occurs on many islands including Trinidad and Tobago. On Trinidad I watched this lizard frequently be chased by the larger teiid, Ameiva ameiva. Food includes insects and other invertebrates. Their burrows are usually very shallow. |
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| The Little Striped Whiptail, Aspidoscelis inornatus Baird, 1859. Photograph of a captive specimen from Arizona. Adult body length reaches 85 mm. The species is widespread in the Chihuahuan Desert of the USA and Mexico. The Little Striped Whiptail inhabits grasslands but also occurs in pinon-juniper woodland to elevations of more than 2000 m. They are insectivorous, feeding heavily on beetles and lepidopteron. This species has apparently generated more than a dozen parthenogenetic lineages of whiptail lizards. This lizard was formerly placed in the genus Cnemidophorus. |
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| The Red Tegu, Tupinambis rufescens (Gunther, 1871). Photograph of an animal in the pet trade. Red Tegus are very large, body size reaches at least 500 mm, and the tail may be almost twice the body length, thus specimens may easily reach 1300 mm. The species occurs in Argentina, Brazil, and Paraguay. and it is hunted for its skin. It breeds in the spring (November-December). Average clutch size is 21 eggs, and females don't become sexually mature until they are 330 mm in body length. |
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| The Common Tegu or Golden Tegu, Tupinambis teguixin (Linnaeus, 1758). Upper animal photographed in Trinidad. The lower animal and the close up of the skin is an animal in the pet trade. Females reach a body length of at least 333 mm, males are somewhat smaller. Tegus are found in almost every habitat, and they will use water to escape potential predation. It is omnivorous feeding on fruits as well as animals of many different kinds. Egg deposition occurs in termite nests, usually above the ground. |
Teiids are a New World family distributed from the northwestern USA eastward to the eastern seaboard and southward through Central American, to extreme southern South America. The greatest diversity of species occurs in the lowland tropics. They range is size from 55 mm to more than 500 mm in body length. Habitats used include deserts, grasslands, and rainforest; and several species are semi-aquatic or aquatic. Many are terrestrial species and feed on insects and fruit, there are a few herbivorous species specialized for eating plant foliage, and others feed on eggs, small vertebrates, and at least one is a snail specialist. Many of these visually oriented lizards are highly active, running, climbing, or swimming for a good portion of their lives and as might be expected from their level of activity some maintain high body temperatures for a reptile (up to 40*C). As a group they tend to have narrow heads, elongated bodies, long tails and robust limbs. There are at least nine genera with more than 110 living species. The fossil record shows this family was more widely distributed in the past with upper Cretaceous fossils from Mongolia. |