Southwestern speckled rattlesnake (Crotalus pyrrhus)
The southwestern speckled rattlesnake is a venomous pit viper in the family Viperidae. GBIF holds 491 licensed U.S. records of it; it reaches our listing threshold in 4 states, most of all California (269), Arizona (186) and Nevada (35). Its observation records peak in May.
Common names: southwestern speckled rattlesnake, Mitchell's rattlesnake, more. Crotalus pyrrhus is a venomous pitviper species found in the southwestern United States and northwestern Mexico. A medium-sized snake, it is found mostly in rocky country, active at night and feeding on small mammals.
From Wikipedia: Crotalus pyrrhus, text under CC BY-SA 4.0.
Is the southwestern speckled rattlesnake poisonous or venomous?
Yes. The southwestern speckled 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 4 of its states), Great Plains rat snake (recorded in 1 of its 4 states) and plains hog-nosed snake (recorded in 1 of its 4 states).
Which states have the southwestern speckled rattlesnake?
The southwestern speckled rattlesnake's U.S. record is concentrated: California alone holds 55% of licensed records. It is listed in 4 states in all; the next are Arizona (186), Nevada (35) and Utah (1).
The count includes 135 records filed under the older name Crotalus mitchellii in Arizona.
| # | State | Records | Share of state snakes | Rank in state |
|---|---|---|---|---|
| 1 | California | 269 | 0.4% | 27th of 46 |
| 2 | Arizona | 186 | 0.9% | 28th of 60 |
| 3 | Nevada | 35 | 0.9% | 20th of 27 |
| 4 | Utah | 1 | 0.0% | 27th of 28 |
When is the southwestern speckled rattlesnake seen?
Across the U.S., observation records of the southwestern speckled rattlesnake run mostly March through September, peaking in May with 28% of them. Winter (December to February) holds 3% of them.
Where the southwestern speckled rattlesnake is recorded in each state
California
California holds 269 licensed records, the 27th most recorded of 46 snakes listed there. Its observation records in California run mostly March through September, peaking in May; most licensed records come from Riverside County, San Diego County and San Bernardino County. Next come Imperial County (9) and Orange County (7).
Arizona
Arizona holds 186 licensed records, the 28th most recorded of 60 snakes listed there. Most of its licensed records in Arizona come from Maricopa County, Mohave County and Yavapai County. Next come Yuma County (28) and La Paz County (11).
Nevada
Nevada holds 35 licensed records, the 20th most recorded of 27 snakes listed there. Most of its licensed records in Nevada come from Clark County.
Top counties in the U.S.
| # | County | State | Records | Share of U.S. |
|---|---|---|---|---|
| 1 | Riverside County | California | 110 | 22.4% |
| 2 | Maricopa County | Arizona | 79 | 16.1% |
| 3 | San Diego County | California | 73 | 14.9% |
| 4 | San Bernardino County | California | 69 | 14.1% |
| 5 | Clark County | Nevada | 35 | 7.1% |
| 6 | Mohave County | Arizona | 32 | 6.5% |
| 7 | Yavapai County | Arizona | 28 | 5.7% |
| 8 | Yuma County | Arizona | 28 | 5.7% |
| 9 | La Paz County | Arizona | 11 | 2.2% |
| 10 | Imperial County | California | 9 | 1.8% |
| 11 | Orange County | California | 7 | 1.4% |
| 12 | Pima County | Arizona | 4 | 0.8% |
| 13 | Pinal County | Arizona | 3 | 0.6% |
| 14 | Coconino County | Arizona | 1 | 0.2% |
| 15 | Madera County | California | 1 | 0.2% |
How recent are the southwestern speckled rattlesnake records?
Records of the southwestern speckled rattlesnake span old collections and new observations: 47% date from 2017–2026, and the median record is from 2015. The oldest dated record is from 1897; the busiest year was 2024, with 32 records.
| Decade | Records | Share |
|---|---|---|
| 1890s | 1 | 0.2% |
| 1910s | 6 | 1.5% |
| 1920s | 5 | 1.2% |
| 1930s | 24 | 5.9% |
| 1940s | 4 | 1.0% |
| 1950s | 30 | 7.4% |
| 1960s | 40 | 9.8% |
| 1970s | 14 | 3.4% |
| 1980s | 5 | 1.2% |
| 1990s | 19 | 4.7% |
| 2000s | 19 | 4.7% |
| 2010s | 89 | 21.8% |
| 2020s | 152 | 37.3% |
Species recorded in the same counties
Of the 15 counties where the southwestern speckled rattlesnake is most recorded, 15 are also top counties for both the California kingsnake and the gopher snake; no other snake shares more.
| Species | Shared counties |
|---|---|
| California kingsnake | 15 |
| Gopher snake | 15 |
| Glossy snake | 14 |
| Long-nosed snake | 14 |
| Western patch-nosed snake | 14 |
| Coachwhip | 13 |
| Mohave rattlesnake venomous | 13 |
| Sidewinder venomous | 13 |
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.