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Chuckwalla

Chuckwallas are large lizards found primarily in arid regions of the southwestern United States and northern Mexico. Some are found on coastal islands. The six species of chuckwallas are all placed within the genus Sauromalus; they are part of the iguanid family, Iguanidae. The generic name, Sauromalus, is said to be a combination of two ancient Greek words: sauros meaning 'lizard' and omalus meaning 'flat'. The proper ancient Greek word for 'flat' is however homalos (ὁμαλός) or homalēs (ὁμαλής). The common name 'chuckwalla' derives from the Shoshone word tcaxxwal or Cahuilla čaxwal, transcribed by Spaniards as chacahuala. Chuckwallas are stocky, wide-bodied lizards with flattened midsections and prominent bellies. Their tails are thick, tapering to a blunt tip. Loose folds of skin characterize the neck and sides of their bodies, which are covered in small, coarsely granular scales. The common chuckwalla (Sauromalus ater) measures 15 3/4 inches long, whereas insular species such as the San Esteban chuckwalla of San Esteban Island (Sauromalus varius) can measure as long as 30 in. They are sexually dimorphic, with males having reddish-pink to orange, yellow, or light gray bodies and black heads, shoulders, and limbs; females and juveniles have bodies with scattered spots or contrasting bands of light and dark in shades of gray or yellow. Males are generally larger than females and possess well-developed femoral pores located on the inner sides of their thighs; these pores produce secretions believed to play a role in marking territory. The genus Sauromalus has a wide distribution in biomes of the Sonoran and Mojave Deserts. The common chuckwalla (S. ater) is the species with the greatest range, found from southern California east to southern Nevada and Utah and western Arizona, and south to Baja California and northwestern Mexico. The peninsular chuckwalla (S. australis) is found on the eastern portion of the southern half of the Baja California Peninsula. The other species are island-dwelling, so have much more restricted distributions. The Angel Island chuckwalla (S. hispidus) is found on Isla Ángel de la Guarda and surrounding islands off the coast of the Baja California Peninsula. Two rare and endangered species are the Montserrat chuckwalla (S. slevini) found on Islas Carmen, Coronados, and Montserrat in the southern Gulf of California and the San Esteban chuckwalla or painted chuckwalla (S. varius) found on San Esteban Island, Lobos, and Pelicanos. Chuckwallas prefer lava flows and rocky areas typically vegetated by creosote bush and other such drought-tolerant scrub. The lizards may be found at elevations up to 4,500 ft (1,370 m). Primarily herbivorous, chuckwallas feed on leaves, fruit, and flowers of annuals and perennial plants; insects represent a supplementary prey. The lizards are said to prefer yellow flowers, such as those of the brittlebush (Encelia farinosa).

[ "Ecology", "Botany", "Paleontology", "Lizard", "Zoology", "Sauromalus hispidus", "Sauromalus varius", "Sauromalus ater" ]
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