Mexican Garter Snake

Thamnophis eques (Reuss, 1834)

Spanish Name Culebra de Agua Nómada Mexicano
Max. Recorded Length 121.6 cm / 47.9 inches
Range Aguascalientes, Arizona, Chihuahua, Coahuila, Durango, Guanajuato, Guerrero, Hidalgo, Jalisco, Mexico, Mexico City, Michoacan, Morelos, Nayarit, New Mexico, Oaxaca, Puebla, Queretaro, San Luis Potosi, Sonora, Tlaxcala, Veracruz, Zacatecas
Pet Trade Availability ★☆☆☆ rarely available
Captivity Rating ★★☆☆ fair

Note: These species pages are in various stages of completion. Some are basically finished; others are very much under construction. Please be patient while I work on this section.


In 2003 Roger Conant published an article, based on fieldwork dating back to the early 1960s, identifying seven new subspecies endemic to lakes in Mexico’s transvolcanic belt.


El Carmen Garter Snake
Thamnophis eques carmenensis Conant, 2003
Cuitzeo Garter Snake
Thamnophis eques cuitzeoensis Conant, 2003
Melanistic subspecies from the Lago de Cuitzeo area.
Atotonilco-Cajititlan Garter Snake
Thamnophis eques diluvialis Conant, 2003
Found at “Las Lagunas Atotonilco and Cajititlán and several isolated localities.”
Southern Mexican Garter Snake
Thamnophis eques eques (Reuss, 1834)
Found from Veracruz to Zacatecas.
Zacapu Garter Snake
Thamnophis eques insperatus Conant, 2003
(description). Known from a single specimen.
Northern Mexican Garter Snake
Thamnophis eques megalops (Kennicott, 1860)
Found from Hidalgo to Arizona.
Chapala Garter Snake
Thamnophis eques obscurus Conant, 2003
Patzcuaro Garter Snake
Thamnophis eques patzcuaroensis Conant, 2003
Magdalena Garter Snake
Thamnophis eques scotti Conant, 2003
Blue-striped Mexican Garter Snake
Thamnophis eques virgatenuis Conant, 1963
Found in Chihuaha and Durango at high elevations only; discontinuous range.


Endangered in Arizona and New Mexico, where this species has reportedly been in dramatic decline.

Captive Care

Rossi and Rossi (2003) report very few snakes of this species in captivity. There appears to have been an uptick in interest since then, however; a few breeders appear to be working with several subspecies, and the Cuitzeo Garter Snake in particular seems to be drawing special attention.

It appears to be an unproblematic captive that should be kept at temperatures appropriate to its range; it’s even reportedly a good candidate for switching to a mouse-based diet. However, its protected status throughout its U.S. range, coupled with the general unavailability of snakes from Mexico, make encounters with this species a rare occurrence in the pet and hobbyist trade, though that may be changing.

The Dutch garter snake breeder Steven Bol has pages about the natural history and captive care of the Cuitzeo (cuitzeoensis), Atotonilco-Cajititlan (diluvialis), Zacapu (insperatus), Chapala (obscurus) and Magdalena (scotti) Garter Snakes.

If you have experience with this species and would like to share, please contact me.

For general information on keeping garter snakes in captivity, please see the Care Guide.

Articles and News


Bol, Steven. “Exciting observations on two sympatric Garter Snakes in ‘La Laguna de Chapala,’ Mexico.”

———. “The rediscovery of Thamnophis eques insperatus (the Zacapu Mexican Garter) in Zacapu, Michoacán, Mexico.”

——— and Herbert Bruchmann. “Scott’s Mexican Garter Snake (T. eques scotti, Conant, 2003) in the wild and in captivity.”

Conant, Roger. 2003. “Observations on Garter Snakes of the Thamnophis eques Complex in the Lakes of Mexico’s Transvolcanic Belt, with Descriptions of New Taxa.” American Museum Novitates 3406.

Ernst, Carl H. and Evelyn M. Ernst. 2003. Snakes of the United States and Canada. Washington: Smithsonian Books.

Liner, Ernest A. 1994. Scientific and Common Names for the Amphibians and Reptiles of Mexico in English and Spanish. SSAR Herpetological Circular No. 23.

Rossi, John V. and Roxanne Rossi. 2003. Snakes of the United States and Canada: Natural History and Care in Captivity. Malabar FL: Krieger.

Rossman, Douglas A., Neil B. Ford and Richard A. Seigel. 1996. The Garter Snakes: Evolution and Ecology. Norman OK: University of Oklahoma Press.