CaliforniaHerps.com

A Guide to the Amphibians
and Reptiles of California


Mearns' Rock Lizard - Petrosaurus mearnsi mearnsi

(Stejneger, 1894)
Click on a picture for a larger view



Mearns' Rock Lizard Range Map
Range in California: Red

Dot-locality Range Map


observation link



SoCalHerpsCover
Android and iPhone App
Electronic Field Guide to the
Reptiles and Amphibians of
Southern California.
Click for More Information.
Available Now at the
iTunes App Store
 and Google Play




Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard
Adult male, San Diego County Adult male, San Diego County Adult, San Diego County
Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard
Adult female, San Diego County Gravid adult female, San Diego County Adult female with breeding colors, Imperial County. © Stuart Young
Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard
  Adult, San Diego County   Adult male, San Diego County
Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard
Adult, San Diego County Adult, Imperial Diego County Hatchling, late September,
San Diego County
Adult, San Diego County
Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard
Adult male, San Diego County Adult, basking in and out of the sun on a Winter day in San Diego County

Gravid adult female, showing orange coloring on head, San Diego County
Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard
Adult, San Diego County,
blending in with the granite background.
Adult, San Diego County Adult, San Diego County © Patrick Briggs Adult, San Diego County © Patrick Briggs
Mearns' Rock Lizard Mearns' Rock Lizard Great Basin Collared Lizard  
Adult, San Diego County © Bruce Edley Adult, San Diego County Mearns' Rock Lizard has small granular scales on the dorsal surfaces, and pointed keeled scales on the tails and limbs.  
       
Habitat
Mearns' Rock Lizard Habitat Mearns' Rock Lizard Habitat Mearns' Rock Lizard Habitat  
Habitat, Imperial County. Mearns' Rock Lizards tend
to prefer massive rock outcrops such as these.
Habitat, San Diego County  
Mearns' Rock Lizard Habitat Speckled Rattlesnake Habitat Mearns' Rock Lizard Habitat  
Habitat, San Diego County Habitat, San Diego County Habitat, San Diego County  
       
Short Videos
Mearns' Rock Lizard Mearns' Rock Lizard Mearns' Rock Lizard  
An adult rock lizard shows its rock climbing and jumping acrobatics, finally doing a defensive push-up display, then a juvenile lizard crawls around the face of a massive rock. Mearns' Rock Lizards in the San Diego county desert. Mearns' Rock Lizards on their rocks including one spotted at night.  
     
Description
 
Size
2.75 - 4.5 inches long from snout to vent (6.6 - 10.6 cm). (Stebbins 2003)

Appearance
A medium-sized flat bodied lizard with a conspicuous narrow black collar around the neck (not bordered in white), and a long thin tail which can grow back if detached.
Wavy dark cross scales are granular except on the legs and the tail where they are strongly keeled.
Color and Pattern
Color is olive, brown, or grayish with many small white or bluish spots.
Bars mark the back, but sometimes these are very faint.
The tail is prominently banded.
The underside is pale with some bluish color on the sides.
The throat is dark and marked with whitish spots.

Melanistic lizards occur in the Mountain Springs area. (Lemm, 2006)
Male / Female Differences
Males have a more pronounced pattern and more blue coloring on the throat than females, and enlarged postanal scales.
Females develop orange on the throat and above the eyes when they are gravid.

Life History and Behavior

Activity
Diurnal, and sometimes crepuscular.
Most activity is probably from March into early Fall, but lizards may come out during warm periods at any time of year.
Remains dormant in rock crevices during cold temperatures.
Most active in the early morning during hot periods.
An excellent climber, able to scale nearly vertical rocks and even run upside down among the rocks.
Territoriality
Males are territorial and defend their territories by bobbing their head up and down.
Defense
Escapes from a pursuer by running to the opposite side of a rock.
Will bite when handled.
Diet and Feeding
Eats a variety of small invertebrates, ants, beetles, flies, caterpillars, spiders, etc. along with flower buds and blossoms, and occasionally small lizards.
Breeding
Breeding takes place in the spring.
Females lay 2 - 6 eggs from  June to August.
Eggs hatch in two months.

Geographical Range
Ranges from San Gorgonio Pass south along the east side of the Peninsular Range mountains south into the northern third of Baja California.
Elevational Range
From near sea level to around 3,600 ft. (1,100 m.)  (Stebbins 2003)

Habitat
Associated with large rocks in shady, narrower parts of canyons, on the desert slopes of mountains. Most common among massive rocks and high rocky cliffs and washes, palm oases, and desert flats where there are large rock outcrops.

Notes on Taxonomy
Two subspecies are still recognized by the S.S.A.R. - P. m. mearnsi and P. m. slevini, (which occurs on two islands in the Gulf of California) however Grismer elevated P. m. slevini to full species status in 1999. (Grismer, L. Lee. 1999. An evolutionary classification of reptiles on islands in the Gulf of California, México. Herpetologica 55 (4): 446-469)

Conservation Issues  (Conservation Status)
None
Taxonomy
Family Phrynosomatidae Zebra-tailed, Earless, Fringe-toed, Spiny, Tree, Side-blotched, and Horned Lizards Fitzinger, 1843
Genus Petrosaurus California Rock Lizards Boulenger, 1885
Species mearnsi Banded Rock Lizard (Stejneger, 1894)
Subspecies

mearnsi Mearns' Rock Lizard (Stejneger, 1894)
Original Description
Petrosaurus mearnsi - (Stejneger, 1894) - Proc. U.S. Natl. Mus., Vol. 17, p. 589

from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz

Meaning of the Scientific Name
Petrosaurus - Greek - petra - rock and sauros - lizard refers to this lizrd's habitat
mearnsi
- honors Mearns, Edgar A.

from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz

Alternate Names
Petrosaurus mearnsi - Banded Rock Lizard (no subspecies recognized)

Related or Similar California Lizards
Baja Collared Lizard

More Information and References
California Department of Fish and Wildlife

Stebbins, Robert C., and McGinnis, Samuel M.  Field Guide to Amphibians and Reptiles of California: Revised Edition (California Natural History Guides) University of California Press, 2012.

Stebbins, Robert C. California Amphibians and Reptiles. The University of California Press, 1972.

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

Behler, John L., and F. Wayne King. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, 1992.

Powell, Robert., Joseph T. Collins, and Errol D. Hooper Jr. A Key to Amphibians and Reptiles of the Continental United States and Canada. The University Press of Kansas, 1998.

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.

Grismer, L. Lee. Amphibians and Reptiles of Baja California, Including Its Pacific Islands and the Islands in the Sea of Cortés. The University of California Press, 2002.

McPeak, Ron H. Amphibians and Reptiles of Baja California. Sea Challengers, 2000.

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

Conservation Status

The following status listings come from the Special Animals List and the Endangered and Threatened Animals List which are published by the California Department of Fish and Wildlife.


This animal is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California.


Organization
Status Listing
U.S. Endangered Species Act (ESA) None
California Endangered Species Act (CESA) None
California Department of Fish and Wildlife None
Bureau of Land Management None
USDA Forest Service None

 

Home Site Map About Us Identification Lists Maps Photos More Lists CA Snakes CA Lizards CA Turtles CA Salamanders CA Frogs
Contact Us Usage Resources Rattlesnakes Sounds Videos FieldHerping Yard Herps Behavior Herp Fun CA Regulations
Beyond CA All Herps


Return to the Top

 © 2000 -