Ridge-nosed rattlesnake (Crotalus willardi)
The ridge-nosed rattlesnake is a venomous pit viper in the family Viperidae. GBIF holds 77 licensed U.S. records of it; it reaches our listing threshold in 2 states, most of all Arizona (71) and New Mexico (6).
Common names: ridge-nosed rattlesnake, Willard's rattlesnake, Willard's rattler Crotalus willardi is a venomous pit viper species found in the southwestern United States and Mexico. This snake is found mainly in the "sky island" region. The IUCN reports this snake's conservation status as being of Least Concern.
From Wikipedia: Crotalus willardi, text under CC BY-SA 4.0.
Is the ridge-nosed rattlesnake poisonous or venomous?
Yes. The ridge-nosed rattlesnake is a pit viper (family Viperidae), like every rattlesnake, copperhead and cottonmouth in the U.S. Its bite needs emergency care: call 911 and keep the bitten limb still. Antivenom is given in hospital.
Snakes often mistaken for it
Species commonly confused with rattlesnakes and recorded in the same states: gopher snake (recorded in all 2 of its states), plains hog-nosed snake (recorded in all 2 of its states) and Great Plains rat snake (recorded in 1 of its 2 states).
Which states have the ridge-nosed rattlesnake?
The ridge-nosed rattlesnake's U.S. record is concentrated: Arizona alone holds 92% of licensed records. It is listed in 2 states in all; the next are New Mexico (6).
| # | State | Records | Share of state snakes | Rank in state |
|---|---|---|---|---|
| 1 | Arizona | 71 | 0.3% | 45th of 60 |
| 2 | New Mexico | 6 | 0.1% | 49th of 56 |
How recent are the ridge-nosed rattlesnake records?
The ridge-nosed rattlesnake record leans on older material: only 29% of dated U.S. records come from 2017–2026, and the median record is from 1991. The oldest dated record is from 1898; the busiest year was 2025, with 5 records.
| Decade | Records | Share |
|---|---|---|
| 1890s | 1 | 2.4% |
| 1920s | 5 | 11.9% |
| 1950s | 4 | 9.5% |
| 1960s | 3 | 7.1% |
| 1970s | 4 | 9.5% |
| 1980s | 2 | 4.8% |
| 1990s | 6 | 14.3% |
| 2000s | 1 | 2.4% |
| 2010s | 5 | 11.9% |
| 2020s | 11 | 26.2% |
Related species in the U.S.
Other species of the genus Crotalus with profiles here: Western rattlesnake, Western diamondback rattlesnake, Prairie rattlesnake, Sidewinder, Timber rattlesnake, Mohave rattlesnake, Red diamond rattlesnake and Black-tailed rattlesnake.
GBIF records read 2026-09-29. Listed: any license. Counted: CC0/CC BY only. How we count.