Leptotyphlops humilis is a blind snake species endemic to the southwestern United States and northern Mexico. It falls within the reptilian class, the squamata order and serpents suborder, the leptotyphlopidae family and the leptotyphlops genus and L. humilis species. It is also known as the rena humilis, stenostoma humile, the glauconia huilis, the siagonodon humilis, and the leptotyphlops chumilis. It is commonly referred to as the western slender blind snake, western threadsnake, western blind snake.
There are nine subspecies of this snake that are currently recognized.
Though it is a snake, the leptotyphlops humilis, like many of the others in its family, resembles a long earthworm. It lives underground in burrows. Because there is little light in its most common environment, it has no use for vision. Accordingly, its eyes are mostly vestigial, but they are believed to be capable of detecting light. The western blind snake is pink, purple, beige or silvery-brown in color, shiny, wormlike, cylindrical, and blunt at both ends, and has light-detecting black eyespots. The snake’s skull is thick to permit burrowing, and it has a spine at the end of its tail that it uses for leverage. It is usually less than twelve inches in total length, including its tail, though some that are almost 16 inches have been noted. It is as large, or only slightly larger, in girth than an earthworm. This species and other blind snakes are fluorescent under low frequency ultraviolet (i.e., black) light.
On the top of the head, between the ocular scales, L. humilis has only one scale
It is found in the southwestern United States, South Florida, and northern Mexico. In the U.S. it ranges from southwestern and Trans-Pecos Texas west through southern and central Arizona, southern Nevada, southwestern Utah, and southern California. In Mexico its distribution includes the Mexican states of Baja California, Sonora, Sinaloa, Nayarit, Jalisco, Colima, Chihuahua, Durango, Coahuila, Tamaulipas, and San Luis Potosí.
The snake lives underground, sometimes as deep as 60 feet. It is known to invade ant and termite nests. Millipedes and centipedes are also occasionally eaten. Its diet is made up mostly of insects and their larvae and eggs. When searching for food, a western blind snake will hunt until it finds an ant pheromone trail and follow it back to the nest to consume the residents. Its smooth, tightly overlapping scales provide protection against the bites and stings of ants. It is found in deserts and scrub where the soil is loose enough to work.
The hard, shiny scales on the underside are similar in appearance to those on the back, except lighter in color. Teeth are lacking from the upper jaw in these creatures.
These snakes will live at altitudes from below sea level to 5,000 feet. The western blind snake prefers moist, loose soils suitable for burrowing. This may include the sandy washes or canyon bottoms of mountain brushy areas or desert grasslands.
If disturbed, it will writhe and wiggle its tail to focus attention here instead of on the head. Preyed upon by a wide variety of animals, including birds, mammals, snakes, fish and even spiders, this tiny serpent shares a feature with the much larger boas and pythons in that it has the remains of a pelvic girdle and femur, complete with a tiny spur.
A secretive, nocturnal snake, blind snakes mate in spring. In late summer the females lay 2 to 7 slender, tiny 5/8 inch long eggs in protected underground nurseries. Sometimes they nest communally. The eggs are tended until after the 3½ inch long hatchlings emerge from their eggs.