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Coluber constrictor mormon - Western Yellow-Bellied Racer
Photo by Chris Brown

Scientific name: Coluber constrictor mormon

Common name: Western Yellow-Bellied Racer

Size: 14.2-29.5 in (36-75 cm)

Distinguishing characters: A slender snake with large eyes and round pupils; smooth scales and brown, olive or bluish on dorsum; white or pale yellow venter; tail long and slender.

Juveniles: Lighter background with brown crossbars or conjoined blotches across back; smaller blotches on sides.

Dimorphism: None

Similar species: Arizona elegans: Has countersunk lower jaw. Pituophis melanoleucas: Has keeled scales. Hypsiglena torquata: Has flat head and vertical pupils. These species can resemble juveniles of Coluber constrictor. Adult Coluber constrictor are fairly distinctive, but could be confused with Thamnophis hammondii (has keeled dorsal scales and yellow side stripes).

Additional notes: A fast moving species that is difficult to capture in the wild. May excrete musk and bite when handled. Prefers grasslands and riparian habitats.

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Last update: 05 March 2003