Species Guide
This section is the most ambitious and the most incomplete. There’s still lots left to do. Want to help?
Garter Snake Species Pages
The core of this section is the thirty 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. In particular, I need written descriptions, photos, and information on their legal status by state and province.
I’d also like to have some decent range maps, but that will definitely take some work.
Clicking on the states and provinces in the range fields will take you to a page for that state and province that lists each indigenous garter snake species.
- Pacific Coast Aquatic Garter Snake, Thamnophis atratus (Kennicott, 1860)
- Short-headed Garter Snake, Thamnophis brachystoma (Cope, 1892)
- Butler’s Garter Snake, Thamnophis butleri (Cope, 1889)
- Golden-headed Garter Snake, Thamnophis chrysocephalus (Cope, 1885)
- 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)
- 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.
Other Natricines
If you’re interested in garter snakes, you might also be interested in other snakes from the same subfamily (or family, depending on which taxonomist you trust), 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.

