California Mountain Kingsnake

California mountain kingsnakes have a banded pattern that consists of red, black, and white crossbands. The bands are always arranged in the same order with each red crossband being surrounded by two black crossbands, forming what is called a triad. Each triad is separated from the next triad by a white crossband, or in some examples by a cream or yellow crossband. Some individuals may have reduced amounts of red pigment, and rare individuals may have virtually no red bands at all. One population from Isla Todos Santos always lacks the red crossbands and is instead uniformly banded with black and white, similar in appearance to the related California kingsnake.

The California mountain kingsnake is endemic to western North America. It ranges from extreme southern Washington state, where it has a disjunct population, through Oregon and California, to northern Baja California. The majority of its range lies within the state of California, which is the reason for its common name.