Species Guide
Garter Snake Species Pages
Each page has some basic data about the species, including length, range, legal status, diet, and availability to (and suitability for) the pet trade. In many cases this information is incomplete, and could use some filling in.
- Pacific Coast Aquatic Garter Snake
Thamnophis atratus (Kennicott, 1860) - Bogert’s Garter Snake
Thamnophis bogerti Rossman and Burbrink, 2005 - Short-headed Garter Snake
Thamnophis brachystoma (Cope, 1892) - Butler’s Garter Snake
Thamnophis butleri (Cope, 1889) - Golden-headed Garter Snake
Thamnophis chrysocephalus (Cope, 1885) - Conant’s Garter Snake
Thamnophis conanti Rossman and Burbrink, 2005 - Sierra Garter Snake
Thamnophis couchii (Kennicott, 1859) - Black-necked Garter Snake
Thamnophis cyrtopsis (Kennicott, 1860) - Western Terrestrial Garter Snake
Thamnophis elegans (Baird and Girard, 1853) - Mexican Garter Snake
Thamnophis eques (Reuss, 1834) - Mexican Wandering Garter Snake
Thamnophis errans (H. M. Smith, 1942) - Exiled Garter Snake
Thamnophis exsul Rossman 1969 - Mesoamerican Highlands Garter Snake
Thamnophis fulvus (Bocourt, 1893) - Giant Garter Snake
Thamnophis gigas (Fitch, 1940) - Godman’s Garter Snake
Thamnophis godmani (Günther, 1894) - Two-striped Garter Snake
Thamnophis hammondii (Kennicott, 1860) - Liner’s Garter Snake
Thamnophis lineri Rossman and Burbrink, 2005 - Checkered Garter Snake
Thamnophis marcianus (Baird and Girard, 1853) - Mexican Black-bellied Garter Snake
Thamnophis melanogaster (Peters, 1864) - Tamaulipan Montane Garter Snake
Thamnophis mendax Walker, 1955 - Southern Durango Spotted Garter Snake
Thamnophis nigronuchalis Thompson, 1957 - Northwestern Garter Snake
Thamnophis ordinoides (Baird and Girard, 1852) - Tepalcatepec Valley Garter Snake
Thamnophis postremus H. M. Smith, 1942 - Western Ribbon Snake
Thamnophis proximus (Say, 1823) - Yellow-throated Garter Snake
Thamnophis pulchrilatus (Cope, 1885) - Plains Garter Snake
Thamnophis radix (Baird and Girard, 1853) - Rossman’s Garter Snake
Thamnophis rossmani Conant, 2000 - Narrow-headed Garter Snake
Thamnophis rufipunctatus (Cope, 1875) - Eastern Ribbon Snake
Thamnophis sauritus (Linnaeus, 1766) - Mexican Alpine Blotched Garter Snake
Thamnophis scalaris Cope, 1861 - Mesa Central Blotched Garter Snake
Thamnophis scaliger (Jan, 1863) - Common Garter Snake
Thamnophis sirtalis (Linnaeus, 1758) - Sumichrast’s Garter Snake
Thamnophis sumichrasti (Cope, 1866) - Mexican Pacific Lowlands Garter Snake
Thamnophis validus (Kennicott, 1860)
Identification
Identifying a snake’s species is one of the most frequently asked questions about garter snakes, and I hope to have some pertinent information here eventually, including photos, range maps, and maybe even an identification key. But we’re a long way from that right now.
What can you do in the meantime? There’s an identification key in The Garter Snakes by Rossman, Ford and Seigel, but it’s difficult to use: it’s deliberately precise rather than easy.
One thing you can do is reduce the number of candidates. Many people think they have found a snake species that’s impossible for example, they think they’ve found Butler’s Garter Snakes on the West Coast (when they’ve probably found Northwestern Garters). This is usually because they try to find a photo online that best matches what they’ve seen. Unfortunately, some snakes are extremely variable, and others are hard to tell apart.
So what you can do is check your province or state to see what species are found there. The species descriptions should list which subspecies are in that area and subspecies information should be improved in the future. Then start searching the web for photos and use the species names as your search terms.
Canada: Alberta, British Columbia, Manitoba, New Brunswick, Northwest Territories, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan.
United States: Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming.

This map shows the number of garter snake species in each U.S. state. In many states, there are only two species: it’s often just a matter of figuring out whether it’s a garter snake or a ribbon snake. In other states (especially California and New Mexico), it can be much more of a challenge.
Other Natricines
If you’re interested in garter snakes, you might also be interested in their closest relatives, such as brown, red-bellied, queen and water snakes. Here’s a list of North American natricine snakes that I’ve put together. I might add more on natricines later on, depending on how things go.
