Checkered Garter Snake
Thamnophis marcianus • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: T. marcianus
Southwestern United States, including Texas, New Mexico, Arizona, and parts of Oklahoma, extending southward through Mexico to Central America.
Look up Checkered Garter Snake in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: T. marcianus
Conservation
Least Concern, with a stable population and broad distribution across its native range.
Physical Description
Features a distinctive checkered pattern of dark blotches between light-colored stripes on an olive, brownish, or gray background. Scales are strongly keeled, and the body is moderately stout.
Size & Dimensions
Typical adult size ranges from 40 to 90 centimeters in total length.
Habitat
Found near water sources such as streams, rivers, ponds, irrigation ditches, and marshes, but also capable of inhabiting arid and semi-arid grasslands and shrublands.
Diet & Feeding
Feeds primarily on amphibians, fish, earthworms, and small rodents, hunting actively in riparian and aquatic microhabitats.
Reproduction
Viviparous, giving birth to live young. Litter sizes typically range from 6 to 20 offspring, born during the warm summer months.
Look-alikes
Can be confused with other garter snake species within the genus Thamnophis, distinguished primarily by the specific arrangement of lateral spots and head markings.
Conservation Status
Least Concern, with a stable population and broad distribution across its native range.
Cultural Significance
Plays an important ecological role in controlling amphibian and invertebrate populations within its wetland and riparian ecosystems.
Notable Features
Exhibits a prominent checkered dorsal pattern and a light vertebral stripe, providing effective camouflage in grassy and muddy environments.