The western black-headed snake (''Tantilla planiceps''), also known as the California black-headed snake, is a snake species endemic to the Californias (the U.S.

State of California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and the Baja California Peninsula in Mexico), as north as the

San Francisco Bay San Francisco Bay is a large tidal estuary in the U.S. state of California, and gives its name to the San Francisco Bay Area. It is dominated by the big cities of San Francisco, San Jose, and Oakland. San Francisco Bay drains water from a ...

and as far east as western Utah, and Texas. It lives in mostly moist pockets in mostly arid or semiarid environments and spends much of its life underground. It has a flattened head as most crevice-dwellers and is seven to fifteen inches in size. It is brown, slender, olive-gray, with a black head bordered by a white collar. Its habitat is often in woodland, desert areas, grassland and along arroyos in areas that are wet in a usually dry region. The western black-headed snake is a member of a larger natural group of small New World terrestrial colubrids, where some of the related species include sand snake (''Chilomeniscus''), shovel-nosed snake (''Chionactis''), and the ground snake (''Sonora''). The western black-headed snake is the sister species of ''Tantilla yaquia'' of southern Arizona. They are also related to ''

Tantilla gracilis ''Tantilla gracilis'' (flathead snake) is a species of snake of the family Colubridae. Geographic range The snake is found in the US states of Missouri, Texas, Kansas, Illinois, Oklahoma, Louisiana and Arkansas and in Mexico Mexico (Spanis ...

'', ''Tantilla atriceps'', ''

Tantilla hobartsmithi ''Tantilla hobartsmithi'', commonly known as the southwestern blackhead snake, Smith's blackhead snake, or Smith's black-headed snake, is a species of small colubrid snake native to the southwestern United States and northern Mexico. Etymology T ...

'' and ''

Tantilla nigriceps The Plains black-headed snake or Plains blackhead snake (''Tantilla nigriceps'') is a species of snake of the family Colubridae. They are approximately in length, with a uniform tan to brownish-gray. Their ventral scales are white with a pink or ...

'', all species endemic to the

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado, Ne ...

. It is visually similar to the southwestern black-headed snake (''T. hobartsmithi''). Although they usually appear singly or in pairs, as many as six individual snakes have been observed together. They prey on

arthropods Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

, particularly centipedes and beetle larvae, as well as spiders, insects, slugs, and earthworms. They are highly secretive and rarely seen, spending much time under objects, especially during daytime.Stebbins, Robert Cyril (1972). ''Amphibians and Reptiles of California''. University of California Press. Page 5. .

Sources

{{Taxonbar, from=Q2023348 Colubrids Fauna of California Reptiles of Mexico Reptiles of the United States Snakes of North America Reptiles described in 1835