The southwestern blackhead snake (Tantilla hobartsmithi) is a species of small colubrid snake native to the southwestern United States and northern Mexico.
The specific name or epithet, hobartsmithi, is in honor of American zoologist and herpetologist Hobart M. Smith (1912-2013), which sometimes leads it to be referred to as Smith’s black-headed snake.
Taxonomy and Systematics
It was first described by Edward Harrison Taylor in 1936.
The southwestern blackhead snake is a small snake, growing to a maximum total length of 15 in (38 cm), but typically averaging around 8 in (20 cm) in total length.
Dorsally, it is uniformly brown in color, except for the black-colored head, which gives it its common name, and a cream-colored or white collar. On the belly, there is a broad reddish stripe, which runs down the center of the ventral scales.
It is rear-fanged, having enlarged rear teeth and a modified saliva, which while harmless to mammals, is believed to be toxic to arthropods, their primary prey.
Blackhead snakes are primarily nocturnal and fossorial, spending most of their time hiding in loose soil, leaf litter, or under ground debris.
They eat most varieties of soft-bodied insects and centipedes.
The southwestern blackhead snake is found in the southwestern United States, in Arizona, California, Colorado, Nevada, New Mexico, Texas, and Utah, as well as in northern Mexico, in Chihuahua, and Coahuila, and Sonora.
In California, it was sighted in Darwin Falls, Death Valley National Park, on May 18 of 2012, and in Jamul on May 16 of 2016. It has also been seen in Sedona Arizona of Yavapai County on April 11, 2005.
In Texas, it was found in Big Bend National Park on April 25, 2010. …seen in HM&FEW’s GARDEN (Roswell, New Mexico) on April 30, 2016.