Coluber mormon, a Species Distinct from C. constrictor

Abstract

For more than 100 years Coluber constrictor mormon has been recognized as a subspecies of the eastern racer. However, trenchant differences exist between mormon and the neighboring C. c. flaviventris in numbers of maxillary and dentary teeth, and there are even greater differences in ecological traits including relative size of egg and number of eggs per clutch. Also, there are average differences in body size, proportions, color, numbers of juvenile blotches, and numbers of supralabials, subcaudals and ventrals, but individual variation results in some overlap in each of these characters. The geographic ranges are widely separated by the physical barrier of the Rocky Mountains, and there is no intergradation. The Western Yellow-bellied Racer should be restored to its original status of a full species, Coluber mormon.