Hypsiglena chlorophaea deserticola - Northern Desert Nightsnake

Mildly Venomous

Not considered dangerous to humans.

Size

Adults can be 12 - 26 inches long (30-66 cm.) Most seen are 8 - 12 inches long, rarely over 16 inches. Hatchlings are about 7 inches in length.

Appearance

A small slender snake with a narrow flat head, smooth scales in 21 rows, and vertical pupils. Color varies, often matching the substrate, from light gray, light brown, beige, to tan or cream, with dark brown or gray blotches on the back and sides. Usually a pair of large dark markings on the neck and a dark bar through or behind the eyes. Whitish or yellowish and unmarked underneath.

Behavior

Nocturnal, and also active at dusk and dawn. Can be found under rocks, boards, dead Joshua tree branches, and other surface objects. Often seen crossing desert roads on warm nights.

Diet

Eats a wide range of terrestrial vertebrates, mostly lizards and their eggs, sometimes small snakes, frogs, and salamanders.

Reproduction

Lays eggs from April to September.

Range

This subspecies, Hypsiglena chlorophaea deserticola - Northern Desert Nightsnake, is found throughout southern California, north to San Luis Obispo County, east and north along the western Sierra Nevada mountains, and into the Great Basin desert in the far northeast part of California, including Lava Beds National Monument. There is also a record for Siskiyou county north of Yreka near the Oregon Border, and an old record from Santa Cruz Island. Ranges south into Baja California, east throughout the southwest, and north into Washington.

The species, Hypsiglena chlorophaea - Desert Nightsnake, occurs from southern California north, east of the Sierra Nevada, into British Columbia, Canada, and east into Idaho, Utah, Colorado, Arizona, New Mexico Kansas, Oklahoma, and Texas and south into Mexico and Baja California, Mexico.

Habitat

Found in a variety of habitats, often arid areas, from chaparral, Sagebrush flats, deserts, suburban lots and gardens, mountain meadows, grassland. Most commonly found in areas with abundant surface cover. Sea level to 8,700 ft. (2,650 meters).

Taxonomic Notes

The Society for the Study of Amphibians and Reptiles based their 2008 list of scientific and common names on Mulcahy (2006, PhD dissertation, Utah State University). Mulcahy conducted a comprehensive genetics study of Hypsiglena, recognizing 6 species, three in the USA, and an undescribed species. He also maintained several subspecies designations.

Grismer et al. (1994 Bulletin of the Southern California Academy of Science 93(2): 45-80) synonymized the Hypsiglena torquata subspecies deserticola and klauberi because they intergraded widely.