A Guide to the Amphibians
and Reptiles of California

Charina umbratica - Southern Rubber Boa

Click on a picture for a larger view

Range in California: Green & Orange

Red: Coastal Rubber Boa

iPhone App
Electronic Field Guide to the
Reptiles and Amphibians of
Southern California
Available Now at the
iTunes App Store.

Adult, San Bernardino County

Adult, 6,100 ft.
San Bernardino County

Juvenile, San Bernardino County

Juvenile, 6,200 ft.
San Bernardino County

Habitat

Habitat,6,200 ft.
San Bernardino County

Habitat, 5,800 ft.
San Bernardino County

Habitat,6,200 ft.
San Bernardino County

Habitat, 4,600 ft., Kern County

Habitat, 5,800 ft.
San Bernardino County

Description

Nonvenomous

Considered harmless to humans.

Size

Typical size of adults is small - 11 - 15 inches.

Appearance

A small constrictor with a stout body and smooth shiny small-scaled loose and wrinkled skin which gives the snake a rubbery look and feel. Uniform in dorsal color - light brown, dark brown, pink, tan, or olive-green above, and yellow, orange, or cream colored below. Usually no pattern below, but sometimes there is dark mottling. Young snakes are pink or tan, and can be brightly-colored. Eyes are small with vertically elliptical pupils.

The tail is short and blunt and looks like a head. When threatened, the snake hides its head in its coiled body, and elevates the tail to fool an attacker into attacking the tail. Snakes with scarred tails are common.

Behavior

Nocturnal and crepuscular, sometimes active in daylight. Sometimes active in weather that would be too cold for most reptiles, with surface temperatures in the 50s. A good burrower, climber and swimmer. Often found under logs, boards and other debris, sometimes on roads at dusk.

Diet

Eats small mammals, birds, and, lizards.

Reproduction

Breeds from April to June, bearing 2 - 8 live young in late summer or early autumn.

Range

Endemic to California.

Found in a few disjunct areas in montane southern California in the San Bernardino, San Jacinto Mountains.
Boas occuring in the southern Sierra Nevada, the Tehachapi Mountains, and Mt. Pinos are classified as C. umbratica by the California Department of Fish and Wildlife, although their species status is still unclear. These could turn out to be C. umbratica or C. bottae or intergrades.

Boas were found in 2006 and 2010 at Montana de Oro on the coast of San Luis Obispo County, with photo confirmation in 2010, but with no specimens to examine or DNA samples to test, the species cannot be confirmed. However, Stebbins & McGinnis (2012) state that C. umbratica occurs in the "northern part of the South Coast Range" which should include Montana de Oro.

Habitat

Inhabits Oak-conifer and mixed-conifer forests at elevations between roughly 5,000 to 8,200 ft. where rocks and logs or other debris provide shelter.

Taxonomic Notes

The California Departent of Fish and Wildlife describes the range of the Southern Rubber Boa (Charina umbratica) in a 2004 document: "…known from several localities in the San Bernardino Mountains in San Bernardino County, near Idyllwild in Riverside County, and on Mount Pinos in Kern County. … The southern rubber boa … occurs in the San Jacinto Mountains. … Possible intergrades between the southern rubber boa and the rubber boa found in the Tehachapi Mountains and on Mt. Pinos warrant further study.

mtDNA work has shown that most (but not all) Charina in the southern Sierra Nevada and the Tehachapis are more closely related to Charina bottae than to Charina umbratica. "Morphologically, the Kern Plateau, Breckenridge Mountain, Piute Mountains, Scodie Mountains, and Tehachapi Mts populations all are comprised of "dwarf-morph" snakes [similar to C. umbratica] but that trait does not track with the mtDNA." (R.H. Pers. Comm.) Because the morphology does not correspond to the mtDNA findings, there is not enough evidence to support an argument that these populations belong to either species. Until that evidence is found and published, I will continue to show the ranges of Charina in California according to the CDFW interpretation because C. umbratica is a protected species. Since the species status of Charina occuring in the southern Sierra Nevada, the Tehachapi Mountains, Mt. Pinos, and in San Luis Obispo County is still unclear, I will show them separately as classified as C. umbratica by the CDFW on the range map. 4/13

Formerly, one species of Charina was recognized, Charina bottae, with three subspecies.

Some herpetologists still only recognize one species of Charina, Charina bottae, with either no subspecies or with two subspecies - Charina bottae bottae - Northern Rubber Boa, and Charina bottae umbratica - Southern Rubber Boa.

Others recognize two full species of Charina, as is done on this site - Charina bottae - Northern Rubber Boa, and Charina umbratica - Southern Rubber Boa.

Conservation Issues (Conservation Status)

Common where it occurs, this snake is considered a threatened species due to development and habitat degredation in its limited range.

Taxonomy
Family	Boidae	Boas and Pythons
Genus	Charina	Rubber Boas
Species	umbratica	Southern Rubber Boa
Original Description
Charina bottae - (Blainville, 1835) - Nouv. Ann. Mus. Hist. Nat. Paris, Vol. 4, p. 289, pl. 26, figs. 1, 1B from Original Description Citations for the Reptiles and Amphibians of North America © Ellin Beltz
Meaning of the Scientific Name
Charina - Greek -charieis - graceful, delightful from Scientific and Common Names of the Reptiles and Amphibians of North America - Explained © Ellin Beltz umbratica - Latin - umbraticus - belonging to shade, belonging to seclusion from Jaeger, Edmund C. A Source-book of Biological Names and Terms Third Edition. Charles C. Thomas Publisher, 1962.
Alternate Names
Charina bottae - Rubber Boa Charina bottae umbratica
Related or Similar California Snakes
C. bottae - Northern Rubber Boa
More Information and References
Natureserve Explorer California Dept. of Fish and Game 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 Snakes of Western North America (North of Mexico) and Hawaii. University Press of Florida, 2009. Bartlett, R.D. , & Alan Tennant. Snakes of North America - Western Region. Gulf Publishing Co., 2000. Brown, Philip R. A Field Guide to Snakes of California. Gulf Publishing Co., 1997. Ernst, Carl H., Evelyn M. Ernst, & Robert M. Corker. Snakes of the United States and Canada. Smithsonian Institution Press, 2003. Wright, Albert Hazen & Anna Allen Wright. Handbook of Snakes of the United States and Canada. Cornell University Press. Thelander, Carl G., editor in chief. Life on the Edge - A Guide to California's Endangered Natural Resources - Wildlife. Berkeley: Bio Systems Books, 1994.

Conservation Status
The following status listings come from the Special Animals List which is published by the California Department of Fish and Wildlife.
Organization	Status Listing
U.S. Endangered Species Act (ESA)	None
California Endangered Species Act (CESA)	ST	Threatened
California Department of Fish and Wildlife	None
Bureau of Land Management	None
USDA Forest Service	USFS:S	Sensitive
Natureserve Global Conservation Status Ranks	G5T2T3 S2S3	Secure
World Conservation Union - IUCN Red List	None

Return to the Top