Cnemidophorus sonoraeSonoran spotted whiptail

Geographic Range

Cnemidophorus sonorae ranges from southeastern Arizona to northeast Sonora, and east into New Mexico (Case 1990, McAllister 1992). This lizard prefers elevations between 3200 and 8000 feet (Goldberg et al. 1997).

Habitat

These lizards inhabit semi-arid to arid habitats within their range in western North America. These habitats include oak woods and oak savanna, streamside woods, desert grasslands, and desert scrublands (Goldberg et al. 1997, Case 1990, Routman and Hulse 1984, Stebbins 1985).

Physical Description

Snout to vent length is 62-87 mm.

This lizard has six dorsal stripes with five to eight dorsal scales between the middorsal stripes. Overall color is blackish brown or reddish, with white, tan or yellowish spots dorsally and the tail is often a dull orange-tan that tapers to olive at the tip. The belly is cream-colored, and unmarked (Stebbins 1985).

Reproduction

Cnemidophorus sonorae is a unisexual, all-female species that breeds by parthenogenesis (Goldberg et al. 1997, Routman and Hulse 1984, Porter et al. 1994). Ovulation is often stimulated by "pseudocourtship" among the females; the unfertilized eggs develop into hatchlings that are genetically identical to their mothers. Their reproductive season occurs from mid May into late July. Two or three clutches of three to four eggs may be produced annually. Shelled oviductal eggs have an average length of 14.25 mm and a mass of 0.53 g (Routman and Hulse 1984). Eggs are buried in the ground; based on studies of related species, the incubation period is probably around 40 to 60 days.

Behavior

This species has a bimodal daily activity pattern. They are generally active from about 0830 to 1130 hrs and then rest during the intense heat of the day, resuming activities in the afternoon from 1400 to 1700 hrs. The peak activity is during the morning session. Their fat storage remains low for most of their seasonal activities and increases slightly before brumation (dormancy) begins in late summer or fall (Routman and Hulse 1984).

Food Habits

This lizard feeds largely on small animals with an average length of 1.28 mm numerically and 1.80 mm volumetrically (Goldberg et al. 1997). Prey is mostly insects and other invertebrates. In captivity they have eaten chicken mash (Porter et al. 1994).

Economic Importance for Humans: Positive

Lizards are useful in the control of insect pests; they fill an important ecological niche as small predators in a number of aridland habitats.

Conservation Status

Other Comments

Common predators of C. sonorae are birds, especially the roadrunner, and many reptiles which they may encounter in burrows. They do have the ability of autotomizing their tails (Routman and Hulse 1984). This may help in the evasion of some predation attempts.

Contributors

Jerry Redding II (author), Michigan State University, James Harding (editor), Michigan State University.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

native range

the area in which the animal is naturally found, the region in which it is endemic.

References

Case, T. 1990. Patterns of coexistence in sexual and asexual species of Cnemidophorus lizards. Oecologia, 83(2): 220-227.

Goldberg, S., C. Bursey, H. Cheam. 1997. Helminths from the Sonoran spotted whiptail, Cnemidophorus sonorae, and the western whiptail, Cnemidophorus tigris (Saurie: Teiidae), from southern Arizona with comments on Abbreviata terrapenis (Nematoda: Physalopteridae). Great Basin Naturalist, 57(3): 273-277.

Jennings, M. 1984. Predation on Sonoran spotted whiptails, Cnemidophorus sonorae (Teiidae), by the great-tailed grackle, Quiscalus mexicanus (Icteridae). Southwest Naturalist, 29(4): 514.

McAllister, C. 1992. Helminth parasites of unisexual and bisexual whiptail lizards (Teiidae) in North America 8. The gila spotted whiptail (Cnemidophorus flagellicaudus), Sonoran spotted whiptail (Cnemidophorus sonorae), and plateau striped whiptail (Cnemidophorus velox). Texas Journal of Science, 44(2): 233-239.

Porter, W., C. Cole, C. Townsend. 1994. Captive maintenance and lineage senescence in parthenogenic lizards (family Teiidae). Contributions to Herpetology, 11: 91-98.

Routman, E., A. Hulse. 1984. Ecology and reproduction of a parthenogenic lizard, Cnemidophorus sonorae. Journal of Herpetology, 18(4): 381-386.

Stebbins, R. 1985. A Field Guide to Western Reptiles and Amphibians. Boston: Houghton Mifflin Company.