The specific epithet marcianus is in honor of American Brigadier General Randolph B. Marcy, who led surveying expeditions to the frontier areas in the mid-19th century.

[3] The checkered garter snake is typically greenish in color, with a distinct, black checkerboard pattern down its back.

[citation needed] T. marcianus were long thought to be nonvenomous, but recent discoveries have revealed that they do in fact produce a mild neurotoxic venom.

T. marcianus cannot kill humans with the small amounts of venom they produce, which is comparatively mild, and they also lack an effective means of delivering it.

[citation needed] The checkered garter snake is frequently available in the exotic pet trade, and makes a hardy captive animal.