Southwestern blackhead snake (Tantilla hobartsmithi)
The southwestern blackhead snake is a snake in the family Colubridae with a mild venom for its prey, not dangerous to people. GBIF holds 383 licensed U.S. records of it; it reaches our listing threshold in 6 states, most of all Arizona (183), Texas (120) and California (51).
Tantilla hobartsmithi, commonly known as Smith's black-headed snake and the southwestern blackhead snake, is a species of small snake in the subfamily Colubrinae of the family Colubridae. The species is native to the southwestern United States and adjacent northern Mexico.
From Wikipedia: Tantilla hobartsmithi, text under CC BY-SA 4.0.
Is the southwestern blackhead snake poisonous or venomous?
Mildly venomous but not dangerous: the southwestern blackhead snake has enlarged rear teeth and a mild venom for its prey, and a bite causes at most local swelling, which is why many sources simply call it harmless. It is not a pit viper or coral snake, the only U.S. land snakes with medically dangerous venom. Clean any bite like a small wound.
Which states have the southwestern blackhead snake?
Records are spread over 6 states; the top three, Arizona, Texas and California, hold 92% of them.
| # | State | Records | Share of state snakes | Rank in state |
|---|---|---|---|---|
| 1 | Arizona | 183 | 0.9% | 29th of 60 |
| 2 | Texas | 120 | 0.3% | 53rd of 86 |
| 3 | California | 51 | 0.1% | 41st of 46 |
| 4 | New Mexico | 11 | 0.2% | 43rd of 56 |
| 5 | Nevada | 9 | 0.2% | 27th of 27 |
| 6 | Utah | 8 | 0.2% | 23rd of 28 |
Where the southwestern blackhead snake is recorded in each state
Arizona
Arizona holds 183 licensed records, the 29th most recorded of 60 snakes listed there. Most of its licensed records in Arizona come from Pima County, Maricopa County and Pinal County. Next come Yavapai County (17) and Cochise County (13).
Texas
Texas holds 120 licensed records, the 53rd most recorded of 86 snakes listed there. Most of its licensed records in Texas come from El Paso County, Reagan County and Brewster County. Next come Hudspeth County (12) and Presidio County (9).
California
California holds 51 licensed records, the 41st most recorded of 46 snakes listed there. Most of its licensed records in California come from Inyo County, San Bernardino County and Tulare County. Next come Kern County (4) and Riverside County (3).
Top counties in the U.S.
| # | County | State | Records | Share of U.S. |
|---|---|---|---|---|
| 1 | Pima County | Arizona | 53 | 13.8% |
| 2 | Maricopa County | Arizona | 48 | 12.5% |
| 3 | Pinal County | Arizona | 28 | 7.3% |
| 4 | El Paso County | Texas | 28 | 7.3% |
| 5 | Reagan County | Texas | 20 | 5.2% |
| 6 | Inyo County | California | 18 | 4.7% |
| 7 | Yavapai County | Arizona | 17 | 4.4% |
| 8 | Brewster County | Texas | 17 | 4.4% |
| 9 | San Bernardino County | California | 15 | 3.9% |
| 10 | Cochise County | Arizona | 13 | 3.4% |
| 11 | Hudspeth County | Texas | 12 | 3.1% |
| 12 | Graham County | Arizona | 9 | 2.3% |
| 13 | Tulare County | California | 9 | 2.3% |
| 14 | Presidio County | Texas | 9 | 2.3% |
| 15 | Jeff Davis County | Texas | 8 | 2.1% |
How recent are the southwestern blackhead snake records?
The southwestern blackhead snake record leans on older material: only 5% of dated U.S. records come from 2017–2026, and the median record is from 1972. The oldest dated record is from 1912; the busiest year was 1970, with 30 records.
| Decade | Records | Share |
|---|---|---|
| 1910s | 12 | 3.9% |
| 1920s | 2 | 0.7% |
| 1930s | 12 | 3.9% |
| 1940s | 7 | 2.3% |
| 1950s | 18 | 5.9% |
| 1960s | 70 | 23.0% |
| 1970s | 59 | 19.3% |
| 1980s | 28 | 9.2% |
| 1990s | 35 | 11.5% |
| 2000s | 22 | 7.2% |
| 2010s | 27 | 8.9% |
| 2020s | 13 | 4.3% |
Species recorded in the same counties
Of the 35 counties where the southwestern blackhead snake is most recorded, 31 are also top counties for the gopher snake, more than for any other snake. Venomous species among its neighbors: the Mohave rattlesnake and the western diamondback rattlesnake.
| Species | Shared counties |
|---|---|
| Gopher snake | 31 |
| Long-nosed snake | 27 |
| Coachwhip | 23 |
| Glossy snake | 23 |
| Mohave rattlesnake venomous | 23 |
| Striped whipsnake | 22 |
| Western diamondback rattlesnake venomous | 22 |
| Western threadsnake | 22 |
Related species in the U.S.
Other species of the genus Tantilla with profiles here: Flathead snake, Plains black-headed snake and Southeastern crown snake.
GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.