Description: The snake is blue-grey to olive-grey, or greenish to brown, and it has brown, orange, or black spots on the back. The total length of adults is 81–112 cm (32–44 in) (about 81–112 cm). It has eight or 9 upper labial scales, one of which enters the eye, two or three preocular scales, two to four postoculars, and one anterior temporal scale. The keeled dorsal scales are arranged in 21 rows at midbody. Ventrals number 152–177; the anal plate is entire; the subcaudals number 65–87, and are divided.

Habitat: It is found near river banks or streams. It is one of the most aquatic of all garter snakes.

Range: It is found in Arizona and New Mexico, and in the Mexican states of Sonora, Chihuahua and Durango.

Found in these States: AZ | NM

Diet: These snakes are piscivorous, meaning they primarily eat fish. Their diet includes dace, chubs, and both native and introduced trout. They might occasionally prey on salamanders.

Reproduction: The mating season is presumed to be in the spring and early summer, with 8-18 young typically born from July to August (Rossman et al. 1996a, Brennan and Holycross 2006). Gartersnakes give birth to their young, and develop a kind of placentation during pregnancy, presumably with some ability to convey nutrients to, and wastes from, embryos.

Status: The snake has declined in parts of its range, but the International Union for Conservation of Nature (IUCN) has classified it as of "Least concern" because of its wide range, presumably large population, and because the rate of decline is not high. However, its status in Mexico is poorly known; were it in a decline there, it might qualify for a category of higher risk. The decline is attributed to introduced species (bullfrogs Lithobates catesbeianus, fishes, crayfish), habitat loss and alteration, and sometimes, needless killing and excessive collecting.

Taxonomy: