Sonoran Spotted Whiptail - Aspidoscelis sonorae

This information is based on previous descriptions of two species which were merged into one - Aspidoscelis flagellicauda and Aspidoscelis sonorae.


The ground color is blackish, brown, or reddish.
There are 6 distinct light-colored longitudinal stripes on the back and sides.
Light spots are present in the dark fields between the stripes. Spots that are lighter in color than the light stripes may also extend onto the stripes. Older individuals tend to be more heavily spotted.
The underside is cream colored and not marked.

Range In California

Established in Orange County:
Discovered in Irvine, they have also been found in surrounding communities where they continue to spread.

Also reported from:

San Diego County in Oceanside:
Los Angeles County in the city of Los Angeles, where they could also be established;
Sacramento County - northeast of Sacramento. iNaturalist reports show at least one juvenile so they are apparently established.


Native Range (Shown on map below)

Ranges across central and southeast Arizona into New Mexico with an isolated poulation in the Chiricahua and Catalina Mountains of Arizona, and south into the northern parts of the states of Chihuahua and Sonora in Mexico.

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Original Discovery in California

In April 2015 a population of alien whiptails observed in Irvine in May 2014 was reported on iNaturalist.org.

Ryan S. Winkleman & Adam R. Backlin published a note in June 2016 * documenting non-native whiptails they found in Irvine. Experts could not identify the exact species and called them "Aspidoscelis flagellicauda/sonorae complex (Spotted Whiptail)."

"Presumably introduced as a single released/escaped pet that subsequently underwent asexual reproduction and established a small, localized population." * These whiptails are all females that reproduce with unfertilized eggs, which allows them to colonize and spread quickly from just one female. Both adults and juveniles were observed, showing that they have established a population. Although the authors concluded that the whiptails were apparently extirpated from the original observation site, Ryan Winkleman informed me that after the note was published several whiptails were observed there, indicating that they are still extant there. I have also received a personal communication from a biologist who observed a few whiptails in June 2016 while conducting a bird survey about two miles from the originally documented area.

The authors also mention that at least one similar whiptail was observed in the neighboring city of Lake Forest, suggesting that the whiptails are more widespread in the region and possibly expanding their range. (I have received other reports that they are well-established there now.)

According to Winkleman and Backlin "The Aspidoscelis flagellicauda/sonorae complex are triploid unisexuals which makes it difficult, if not impossible, to identify these lizards to the species level with just mtDNA. To complicate the identification further, many of the morphological characters that are used to differentiate A. flagellicauda from  A. sonorae, including pre-anal scale counts, number of granules between the paravertebrals, and the number of scales around mid-body, were not useful in narrowing the identification. The collected specimens, as examined by Greg B. Pauly, were found in each case to have one character that would favor identification as one species and another contradictory character that would favor identification as the other species. For the purpose of this note, because the specimens are non-native and apparently extirpated from the collection site, [it was later shown that they are not extirpated from the site] we feel that identification to species is not significant and may not be possible without nuclear sequence data due to the aforementioned circumstances."
[Ryan S. Winkleman & Adam R. Backlin, Herpetological Review 47(2), 2016)]

The lizards introduced into California were originally identified as hybrids of two whiptail species - Aspidoscelis flagellicaudus - Gila Spotted Whiptail and Aspidoscelis sonorae - Sonoran Spotted Whiptail.

Stebbins, Robert C. A Field Guide to Western Reptiles and Amphibians. 3rd Edition. Houghton Mifflin Company, 2003.

Bartlett, R. D. & Patricia P. Bartlett. Guide and Reference to the Turtles and Lizards of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009.

Jones, Lawrence, Rob Lovich, editors. Lizards of the American Southwest: A Photographic Field Guide. Rio Nuevo Publishers, 2009.

Smith, Hobart M. Handbook of Lizards, Lizards of the United States and of Canada. Cornell University Press, 1946.