Coachella Valley Fringe Toed Lizard

The Coachella Valley fringe-toed lizard is well adapted to its sandy habitat, with the fringes on the feet providing not only fast movement over the sand, but enabling the lizard to effectively 'swim' through the sand as it buries deep to escape either the hottest parts of the day or predators (2). When not buried in sand, or sheltering in abandoned rodent burrows (4), the Coachella fringe-toed lizard may dash between patches of shade as it feeds on a diet consisting largely of insects, but also parts of succulent plants (2). The exact composition of the diet of this lizard has been observed to vary depending on the times of the year, with flowers and plant-dwelling arthropods being consumed in abundance during spring when many plants bloom, and then as these foods decline, more leaves, ants and ground arthropods being eaten (5). The hatchlings of other lizards are also sometimes eaten, as well as shed skin, which is believed to help the lizard conserve vital protein (5). Between April and August, the Coachella Valley fringe-toed lizard lays clutches of two to four eggs, with hatchlings appearing between June and September. This lizard reaches sexual maturity at the age of two (4). Periods of drought are known to reduce reproduction in the Coachella Valley fringe-toed lizard (4).

The Coachella Valley fringe-toed lizard is listed as threatened in the United States under the Endangered Species Act, and as an endangered species by the State of California (3). In addition to this legislation, some of this lizard's habitat receives much-needed protection. In 1985, the Coachella Valley National Wildlife Refuge was established to protect the fringe-toed lizard (3), followed by the creation of the Coachella Valley Preserve, which encompasses an additional area of lizard habitat adjacent to the Wildlife Refuge (6). Few lizards now exist outside of these protected areas (1), and thus the continued existence of this refuge and preserve are essential for the survival of this rare and unique reptile.

The Coachella Valley fringe-toed lizard is a small, highly specialised reptile (3), suited to a life on continually shifting sands. The scaly fringes along the toes of the feet, after which this lizard is named, enable it to move with ease across and through sand, while thick, serrated eyelids prevent sand from getting in the eyes (2). Its body is covered with small, smooth scales, forming a striking pattern of black markings on a light grey or white background colour. This distinct network of black lines breaks up on the sides of the bodies and the limbs, where small, black spots speckle the greyish background instead The tail, which is typically longer than the body, is broad and flat (2).

The Cochella Valley fringe-toed lizard has rather unique habitat requirements, occurring only on sand dunes and sandy flats (2) (4), from sea level up to elevations of about 490 metres (1). It requires loose sand in which to burrow and some vegetation for shelter and food (4).

Coachella Valley in Riverside County, California, is the only place you will find this fringe-toed lizard (2). It once had a range that covered just less than 700 square kilometres, but this has been reduced to about 130 square kilometres (3).

Classified as Endangered (EN) on the IUCN Red List (1).

This Endangered reptile has been greatly affected by the loss of its very specific habitat. Human development and the invasion of exotic plant species have taken their toll on at least 80 percent of suitable habitat in the Coachella Valley, and the remaining portion has been fragmented by roads and railways (3) (4). Buildings and invasive plant species both stabilise the once free-moving sands, preventing the continual replenishment of loose sand on which the lizard relies (3).

The Coachella Valley Fringe-toed Lizard has specialized feet that give them their unique name. The lizard has scaly fringes across its toes that allow it to travel easily through thick sand. The webbed-like feet allow the lizard to both move quickly on top of sand and dig quickly through the sand to escape from the hottest parts of the day or predators. The lizard also has serrated eyelids that present sand from getting in the eye. Coachella Fringe-toed Lizards need these adaptations in order to thrive in their sand dune habitat. The rest of the lizard’s body is covered in smooth scales. They are typically a light tan or grey color with dark lines and spots in different areas of the body. The tail of the Coachella Valley Fringe-toed lizard is often times longer than the lizard itself; the tail is broad and flat.

Since the Fringe-toed Lizard lives in the sand dunes, its diet changes as the surrounding do. Mostly, the lizard eats leaves, buds, seeds, and small insects. This diet determines the lizard to be omnivorous. Common predators of the Coachella fringe-toed Lizard are snakes, falcons, roadrunners, badgers, and coyotes.

This taxon is found in the Sonoran Desert, which comprises much of the state of Sonora, Mexico, most of the southern half of the USA states of Arizona, southeastern California, most of the Baja California peninsula, and the numerous islands of the Gulf of California. Its southern third straddles 30° north latitude and is a horse latitude desert; the rest is rainshadow desert. It is lush in comparison to most other deserts. There is a moderate diversity of faunal organisms present, with 550 distinct vertebrate species having been recorded here.

The visually dominant elements of the landscape are two lifeforms that distinguish the Sonoran Desert from the other North American deserts: legume trees and large columnar cacti. This desert also supports many other organisms, encompassing a rich spectrum of some 2000 species of plants, 550 species of vertebrates, and untolled thousands of invertebrate species.

The Sonoran Desert prominently differs from the other three deserts of North America in having mild winters. Most of the area rarely experiences frost, and the biota are partly tropical in origin. Many of the perennial plants and animals are derived from ancestors in the tropical thorn-scrub to the south, their life cycles attuned to the brief summer rainy season. The winter rains, when ample, support great populations of annuals (which make up nearly half of the plant species). Some of the plants and animals are opportunistic, growing or reproducing after significant rainfall in any season.

Creosote Bush (Larrea divaricata) and White Bursage (Ambrosia dumosa) vegetation characterize the lower Colorado River Valley section of the Sonoran. The Arizona upland section to the north and east is more mesic, resulting in greater species diversity and richness. Lower elevation areas are dominated by dense communities of Creosote Bush and White Bursage, but on slopes and higher portions of bajadas, subtrees such as palo verde (Cercidium floridum, C. microphyllum) and Ironwood (Olneya tesota), saguaros (Carnegiea gigantia), and other tall cacti are abundant. Cresosote Bush (Larrea tridentata) and White Bursage (Ambrosia dumosa) form the scrub that dominates the northwest part of the Sonoran Desert. This association thrives on deep, sandy soils in the flatlands. Where the dunes allow for slight inclination of the slope, species of Mesquite (Prosopis), Cercidium, Ironwood (Olneya tesota), Candalia, Lycium, Prickly-pear (Opuntia), Fouquieria, Burrobush (Hymenoclea) and Acacia are favored. The coastal plains of Sonora are composed of an almost pure Larrea scrub. Away from the Gulf influence in the area surrounding the Pinacate, Encelia farinosa, Larrea tridentata,Olneya, Cercidium, Prosopis, Fouquieria and various cacti species dominate the desert.

Many wildlife species, such as Sonoran Pronghorn Antelope (Antilocapra sonoriensis EN), Desert Bighorn Sheep (Ovis canadensis nelsoni) and the endemic Bailey's Pocket Mouse (Chaetodipus baileyi) use ironwood, cacti species and other vegetation as both shelter from the harsh climate as well as a water supply. Other mammals include predators such as Puma (Felis concolor), Coyote (Canis latrans) and prey such as Black-tailed Jackrabbit (Lepus californicus), and the Round-tailed Ground Squirrel (Spermophilus tereticaudus). Other mammals able to withstand the extreme desert climate of this ecoregion include California Leaf-nosed Bat (Macrotus californicus) and Ring-tailed Cat (Bassariscus astutus).

Three endemic lizards to the Sonoran Desert are: the Coachella Fringe-toed Lizard (Uma inornata EN); the Flat-tail Horned Lizard (Phrynosoma mcallii NT); and the Colorado Desert Fringe-toed Lizard (Uma notata NT); an endemic whiptail is theSan Esteban Island Whiptail (Cnemidophorus estebanensis). Non-endemic special status reptiles in the ecoregion include the Desert Tortoise (Gopherus agassizii VU) and the Gila Monster (Heloderma suspectum NT).

There are twenty-fouranuran species occurring in the Sonoran Desert, one of which is endemic, the Sonoran Green Toad (Anaxyrus retiformis). Other anurans in the ecoregion are: California Treefrog (Pseudacris cadaverina); Canyon Treefrog (Hyla arenicolor); Lowland Burrowing Frog (Smilisca fodiens); Mexican Treefrog (Smilisca baudinii); Madrean Treefrog (Hyla eximia); Sabinal Frog (Leptodactylus melanonotus); Northwest Mexico Leopard Frog (Lithobates magnaocularis); Brown's Leopard Frog (Lithobates brownorum); Yavapai Leopard Frog (Lithobates yavapaiensis); Mexican Cascade Frog (Lithobates pustulosus); Mexican Leaf Frog (Pachymedusa dacnicolor); Red Spotted Toad (Anaxyrus punctatus); Sinaloa Toad (Incilius mazatlanensis); Sonoran Desert Toad (Incilius alvarius); Eastern Green Toad(Anaxyrus debilis); New Mexico Spadefoot (Spea multiplicata); Great Plains Toad (Anaxyrus cognatus); Couch's Spadefoot Toad (Scaphiopus couchii); Cane Toad (Rhinella marina); Elegant Narrowmouth Toad (Gastrophryne elegans);Little Mexican Toad (Anaxyrus kelloggi); Great Plains Narrowmouth Toad (Gastrophryne olivacea); and Woodhouse's Toad (Anaxyrus woodhousii).

The Sonoran Desert is recognized as an exceptional birding area. Forty-one percent (261 of 622) of all terrestrial bird species found in the USA can be seen here during some season of the year. The Sonoran Desert, together with its eastern neighbor the Chihuahuan Desert, is the richest area in in the USA for birds, particularly hummingbirds. Among the bird species found in the Sonoran Desert are the saguaro-inhabiting Costa's Hummingbird (Calypte costae), Black-tailed Gnatcatcher (Polioptila melanura), Phainopepla (Phainopepla nitens) and Gila Woodpecker (Melanerpes uropygualis). Perhaps the most well-known Sonoran bird is the Greater Roadrunner (Geococcyx californianus), distinguished by its preference for running rather than flying, as it hunts scorpions, tarantulas, rattlesnakes, lizards, and other prey. The Sonoran Desert exhibits two endemic bird species, the highest level of bird endemism in the USA. The Rufous-winged Sparrow (Aimophila carpalis) is rather common in most parts of the Sonoran, but only along the central portion of the Arizona-Mexico border, seen in desert grasses admixed with brush. Rare in extreme southern Arizona along the Mexican border, the endemic Five-striped Sparrow (Aimophila quinquestriata) is predominantly found in canyons on hillsides and slopes among tall, dense scrub.

Continent: North-America
Distribution: USA (SE California: Coachella Valley, Riverside County)
Type locality: "Colorado Desert, San Diego County, California" (in errore, doubtless from Riverside County, California fide HEIFETZ 1941).

The Coachella Valley fringe-toed lizard (Uma inornata) is a species of phrynosomatid lizard.