Types of centipede snakes

Tantilla is a large genus of small snakes in the family Colubridae, the same sprawling family that holds most of the world's harmless snakes. The genus is centered on the Americas, with members ranging from the southern and central United States through Mexico and Central America into parts of South America. Our database holds 50+ species, which makes Tantilla one of the more diverse genera in the family. Common names for the group include black-headed snakes, crowned snakes, and centipede snakes.

These are diminutive animals. Most species are slender and under 30 to 40 centimeters in total length, with some among the smallest snakes in their range. The body is usually plain tan, brown, gray, or reddish above with a paler belly. The signature mark is on the head: many species have a dark cap, crown, or collar set against a lighter neck band, which is where names like Flat-headed Snake, Black-headed Snake, Plains Black-headed Snake, and Southeastern Crowned Snake come from. The head is small and barely distinct from the neck, an adaptation to a life spent pushing through soil and leaf litter.

Tantilla are fossorial and cryptic, meaning they spend most of their lives underground or hidden beneath rocks, logs, bark, and debris. They are rarely seen in the open and are most often found by people who turn over cover objects. Because of this lifestyle they are easy to overlook and many species are poorly studied, so precise details for individual species are limited. When describing any particular species, rely on what is genuinely documented rather than assuming traits from a relative.

Their diet is specialized toward small invertebrates. They feed heavily on centipedes, insect larvae, and other soft-bodied arthropods, which is the source of the name centipede snake. Tantilla are rear-fanged: they have enlarged grooved teeth at the back of the upper jaw and a mild venom (a Duvernoy's secretion) used to subdue these small prey. This venom is adapted to invertebrates and is not considered medically significant to people, and these snakes are small, secretive, and not inclined to bite. Even so, this is a wild snake and the safe choice is to leave it alone rather than handle it. If anyone is ever bitten by a wild snake and there is concern, do not attempt home first aid; contact US Poison Control at 1-800-222-1222 or local emergency services.

Reproduction in Tantilla is egg-laying (oviparous), with females typically producing small clutches of just one to a few eggs, fitting their small body size. They are secretive and non-aggressive by temperament. For people, the main thing to know is that encountering one usually means a healthy environment with abundant cover and invertebrate prey, and the right response is to observe and let it return to hiding.