Sceloporus magister - Desert Spiny Lizard

In California, found primarily in the Sonoran Desert region from Riverside County south, from the desert slopes of the peninsular mountains east to the Colorado River, south to the Baja California border. Ranges farther east over west central and southern Arizona into southwestern New Mexico and south along the west coast of Mexico. On the Colorado Plateau in northern Arizona and southeast Utah and parts of Colorado and New Mexico, another subspecies, S. m. cephaloflavus - Orange-headed Spiny Lizard, takes over.

A population on the coastal side of the southern California mountains at the lower Sweetwater River, may be introduced. (Lemm, 2006)

Determining the northernmost limit of the range of this species is not possible using the locality data of the specimens used in the Schulte, Macy, and Papenfuss 2006¹ study, or the 2007 Leache, Mulcahy study ² because there are not enough samples in the entire area across San Bernardino County where S. uniformis meets S. magister. My range map may not be accurate in that area. Lizards in Cabazon group with S. magister, and a specimen from Riverside County in Joshua Tree National Park groups with S. magister, so I show the two species meeting near the junction of Riverside and San Bernardino Counties in that area based on the general description that S. uniformis is associated with the Mojave Desert and S. magister the Sonoran Desert. There maybe some overlap between the species, also.

Sceloporus magister taxonomy has been very confusing recently (as of May, 2009). As things stand, Sceloporus magister in California represents either one species, possibly with two subspecies, or two full species, the distribution of which does not follow the distribution of the long-accepted subspecies.

In 1996, Grismer & McGuire (1996 Herpetologica 52(3): 416-427) recommended that no subspecies of S. magister should be recognized.

¹   In 2006, Schulte, Macey, and Papenfuss split S. magister into three species - S. magister, S. uniformis, and S. bimaculosus, with two subspecies of S. magister - S. m. magister, and S. m. cephaloflavus.  However, their sample size was very small which makes it difficult to determine the ranges of these new species in California.

In 2008, the S.S.A.R., whose list this web site follows, adopted the 3 species taxonomy of Schulte et al in the sixth edition of their Scientific and Standard English Names of Amphibians and Reptiles of North America north of Mexico list.
The taxonomy used on this site now follows this re-organization:

S. m. uniformis - Yellow-backed Spiny Lizard and S. m. transversus - Barred Spiny Lizard, has been re-arranged into two species: S. magister - Desert Spiny Lizard, and S. uniformis - Yellow-backed Spiny Lizard.
(You can see a range map of the former species here.)

S. uniformis now contains the entire former S. m. transversus subspecies and part of the S. m. uniformis subspecies - those lizards from the Mojave Desert north into Nevada and the extreme southwest corner of Utah and the extreme northwestern corner of Arizona and two small areas near the Colorado River. The remaining former S. m. uniformis from the Sonoran desert in California east into Arizona and south into Baja California are now S. magister - Desert Spiny Lizard. The subspecies S. m. bimaculosus - Twin-spotted Spiny Lizard has been elevated to full species - S. bimaculosus - Twin-spotted Spiny Lizard.

Subspecies of S. magister are no longer recognized because specimens from closer to the type locality of S. m. cephaloflavus have been found to be part of S. uniformis rather than S. magister.

California Department of Fish and Wildlife

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Flaxington, William C. Amphibians and Reptiles of California: Field Observations, Distribution, and Natural History. Fieldnotes Press, Anaheim, California, 2021.

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

Lemm, Jeffrey. Field Guide to Amphibians and Reptiles of the San Diego Region (California Natural History Guides). University of California Press, 2006.

Brown et. al. Reptiles of Washington and Oregon. Seattle Audubon Society,1995.

Nussbaum, R. A., E. D. Brodie Jr., and R. M. Storm. Amphibians and Reptiles of the Pacific Northwest. Moscow, Idaho: University Press of Idaho, 1983.

St. John, Alan D. Reptiles of the Northwest: Alaska to California; Rockies to the Coast. 2nd Edition - Revised & Updated. Lone Pine Publishing, 2021.



¹   A genetic perspective on the geographic association of taxa among arid North American lizards of the Sceloporus magister complex (Squamata: Iguanidae: Phrynosomatinae)
James A. Schulte II, J. Robert Macey & Theodore J. Papenfuss 2006.
Molecular Phylogenetics and Evolution 39: 873-880

²   Phylogeny, divergence times and species limits of spiny lizards (Sceloporus magister species group) in western North American deserts and Baja California
ADAM D. LEACHE and DANIEL G. MULCAHY
Molecular Ecology (2007) doi: 10.1111/j.1365-294X.2007.03556.

Joseph Grinnell and Charles Lewis Camp. A Distributional List of the Amphibians and Reptiles of California. University of California Publications in Zoology Vol. 17, No. 10, pp. 127-208. July 11, 1917.