The western yellow-bellied racer (Coluber constrictor mormon),Wrobel, Murray (2004). Elsevier's Dictionary of Reptiles. Elsevier. Page 122. . also known as the western yellowbelly racerDegenhardt, William G. and Charles W. Painter (2005). Amphibians and Reptiles of New Mexico. UNM Press. Page 13. . or western racer, is a snake subspecies endemic to the Western United States, including California, Oregon, Washington, Idaho, Nevada, New Mexico, Utah, Montana and Colorado.Booth, Douglas E. (2002). Searching for Paradise: Economic Development and Environmental Change in the Mountain West. Rowman & Littlefield. Page 123. .Matsuda, Brent M. and David M. Green (2006). Amphibians and Reptiles of British Columbia. Royal BC Museum. Page 209. . It is a subspecies of the eastern racer. It is nonvenomousMullally, Linda B. and David (2008). Best Hikes with Dogs: Central California. The Mountaineers Books. Page 27. . and is recognized by its long and very slender shape.Stace-Smith, Richard and Lois Johns (1980). Threatened and Endangered Species and Habitats in British Columbia and the Yukon: Proceedings of the Symposium. The Branch. Page 155. .Brown, Philip (1997). A Field Guide to Snakes of California. Gulf Publishing Company. Page 58. . It is visually similar to the eastern yellow-bellied racer, which is also green, blue or brown with a recognizable yellow underside. Also named for its color, the western yellow-bellied racer is also gray with red or brown blotches when young.Richardson, Adele (2003). North American Racer Snakes. Capstone. Page 15. .Cox, Douglas C. and Wilmer W. Tanner (1995). Snakes of Utah. Brigham Young University. Page 28. .
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