Black-Headed Snake

The black-headed snake is a small, secretive colubrid of the arid southwestern United States and northern Mexico, one of several closely related species in the genus Tantilla known collectively as black-headed snakes. The genus is characterized by small size, plain body coloration, and a dark cap over the head.

It is rarely seen due to its small size and secretive, largely subterranean habits, more often discovered under rocks or debris than while active on the surface.

The species is mildly venomous, possessing weak rear fangs used mainly to subdue small invertebrate prey; it poses no significant danger to humans.

• Very small, slender body with smooth scales
• Plain tan, gray, or reddish-brown coloration above, without body banding
• Distinctive solid black or dark brown cap covering the head and often extending onto the neck as a collar
• Pale, sometimes pinkish or salmon-colored belly
• Adults typically 15-30 cm (6-12 in)
• Head cap is the key identifying feature separating it from similar small, plain colubrids

Inhabits arid and semi-arid habitats of the southwestern United States (Arizona, New Mexico, parts of Texas and Utah) and northern Mexico, including rocky hillsides, desert scrub, and grassland edges. Frequently found under rocks, surface litter, and loose soil.

Secretive and largely fossorial or semi-fossorial, spending most of its time under surface cover or in loose soil, becoming active at dusk and at night, especially after rain. It feeds mainly on centipedes and other soft-bodied invertebrates, using mildly venomous rear fangs to subdue prey. It is not aggressive toward humans and its bite is not medically significant. Reproduction is egg-laying, with small clutches consistent with its tiny body size.