A very flat turtle with a rounded, leathery-skinned, flexible, shell which is keelless and unhinged.
The snout is long with open nostrils on the end.
The limbs are flat with broadly-webbed feet.
Color and Pattern
Color is olive, brown or grayish, sometimes with dark markings which fade with age.
The head and limbs are olive to gray with dark markings.
Two dark-bordered light stripes mark each side of the head, extending from the back of the eye and from the back of the angle of the jaw.
The shell has a yellowish border with a dark line around it.
The carapace is rimmed with pale coloring which is four to five times wider on the rear than on the front and sides.
There are pale conical spiny projections (tubercles) along the rear third of the shell.
The plastron is yellowish and unmarked.
Male / Female Differences
Males are smaller than females with a thick tail that extends beyond the carapace, and their pattern is more contrasted than that of females.
The shell has a sandpaper-like texture.
Females become more blotched and mottled as they get older and have a smoother shell with well-developed warts on the front edge.
Juveniles have prominent dark markings on the head and the limbs and black spots on the shell.
Life History and Behavior
Thoroughly aquatic, but basks out of the water.
Active most of the year, becoming dormant in cold temperatures.
Often remains hidden underwater with the snout extended up to the surface to breathe.
Turtles Walking on Land Do Not Always Need to be Picked Up and Rescued
Turtles sometimes leave the water to search for food, a better place to live, a mate, or to lay their eggs in the spring - typically from March to June. If you see a turtle walking on the land, it is probably not sick or lost, so the best thing you can do for the turtle is to leave it alone. Some people want to help a turtle they think is in danger by picking it up and bringing it home or to a wildlife rehabilitation center, but most of the time this harms the turtle by removing it from the wild without reason. Sometimes turtles do get lost or stranded in yards or on busy roads or somewhere where they may be in danger. If you find one in such a situation, it's ok to move it out of danger, but it's best to leave it in a safe place as close to where you found it as possible.
Difficult to approach, moves very fast on land and in the water.
Capable of scratching vigorously and producing a painful bite if handled.
Diet and Feeding
Predominately carniverous. Eat insects, crayfish, worms, snails, fish, frogs, tadpoles, and reptiles.
Both actively hunts its prey and sits still to ambush passing prey. May also scavenge its food.
From May to August, females crawl onto land to lay 1 or 2 clutches of 3 - 39 eggs on exposed, sunny, sandy banks. Hatchlings emerge from August to October.
In California, it is found in permanent, not temporary, rivers, agricultural canals, drainage ditches, artificial lakes and ponds. Prefers still water with a muddy, sandy, or gravelly bottom, and aquatic vegetation.
The species Apalone spinifera - Spiny Softshell, ranges widely through most of the central and southeastern part of the United States with isolated populations in Montana and extreme southern Canada north of New York, and ranging south into northeastern Mexico.
The subspecies Apalone spinifera emoryi, Texas Spiny Softshell, is native to the Rio Grande and Pecos River drainages in Texas and New Mexico, and the lower Rio Grande Valley in Texas, and northern Mexico. It has also been introduced into parts of Arizona, New Mexico, Nevada, Utah, and Baja California.
Range in California
First introduced into the lower Colorado river, Apalone spinifera emoryi has extended its range west into the Imperial Valley and north to the Salton Sea in Imperial and Riverside Counties and continues to spread farther north in the Coachella Valley.
"Spiny Softshells were introduced to the Colorado and Gila rivers in Arizona around 1900 (Miller 1946, Bury and Luckenbach 1976). From the Colorado River, they presumably moved through irrigation canals and/or the New and Alamo Rivers from Mexico to Imperial County. Museum records show that this species had colonized the Imperial Valley by the 1940s and 1950s."
(David M. Goodward and Mihael D. Wilcox. The Rio Grande leopard frog (Lithobates berlandieri) and other introduced and native riparian herpetofauna of the Coachella Valley, Riverside County, California. California Fish and Game 105(2):48-71; 2019)
Texas Spiny Softshells have also been introduced into many other areas in California, but because of their similarity to other kinds of softshell turtles that are kept as pets and abandoned in the state, it's hard to know exactly what kind of softshell turtle is found at any one location. My range maps should be considered incomplete, and all locations shown may not represent breeding populations.
Notes on Taxonomy
Six subspecies are recognized including one endemic in Mexico.
The former subspecies A. s. hartwegi - Western Spiny Softshell, was synonymized with A. s. spinifera in 2008 by McGaugh et al. (2008, Zoologica Scripta 37:289-304)
Formerly classified in the genus Trionyx (Trionyx spinifera emoryi)
Apalone - Greek - apalos - soft, tender - referring to the soft shell
spinifera - Latin - spina- thorn or spine, and -ifer - bearing - refers to the spine-like tubercules along front edge of upper shell emoryi - honors Emory, William H.
No other turtles, native or introduced, are similar in appearance to the Texas Spiny Softshell. However, sometimes other species of softshell turtles sold as pets or found in Asian food markets are released into the wild.
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.
Flaxington, William C. Amphibians and Reptiles of California: Field Observations, Distribution, and Natural History. Fieldnotes Press, Anaheim, California, 2021.
Samuel M. McGinnis and Robert C. Stebbins. Peterson Field Guide to Western Reptiles & Amphibians. 4th Edition. Houghton Mifflin Harcourt Publishing Company, 2018.
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.
Carr, Archie. Handbook of Turtles: The Turtles of the United States, Canada, and Baja California. Cornell University Press, 1969.
Ernst, Carl H., Roger W. Barbour, & Jeffrey E. Lovich. Turtles of the United States and Canada. Smithsonian Institution 1994.
(2nd Edition published 2009)
Lemm, Jeffrey. Field Guide to Amphibians and Reptiles of the San Diego Region (California Natural History Guides). University of California Press, 2006.
The following conservation status listings for this animal are taken from the October 2021 California "Special Animals List" and the October 2021 "State and Federally Listed Endangered and Threatened Animals of California" list, both of which are produced by multiple agencies and available here: https://www.wildlife.ca.gov/Data/CNDDB/Plants-and-Animals. You can check the link to see if there are more recent lists.
If no status is listed here, the animal is not included on either list. This most likely indicates that there are no serious conservation concerns for the animal. To find out more about an animal's status you can go to the NatureServe and IUCN websites to check their rankings.
This turtle is not included on the Special Animals List, which indicates that there are no significant conservation concerns for it in California.