Venomous snakes and spiders in Utah

Utah's venomous snakes are five rattlesnake species. Together they account for 546 licensed records; the western rattlesnake alone has 78% of them, and the least recorded, the southwestern speckled rattlesnake, has 1.

One widow species (Western black widow: 149 records) is on the Utah list. There is no recluse spider on the Utah list: no recluse species reaches 10 records in the state. Widow bites cause muscle pain and cramps; recluse bites can cause a slow-healing wound. Both are rare and seldom fatal.

Yes. Ten scorpion species are recorded in Utah, from 99 licensed records, the five most recorded: Northern scorpion (34 records), Yellow ground scorpion (17 records), Swollenstinger scorpion (13 records), Serradigitus wupatkiensis (9 records), Arizona bark scorpion (6 records). Every scorpion has venom; only the Arizona bark scorpion's sting is medically significant, and it is on the Utah list.

Beyond the main list, one scorpion species is known from Utah by only eight records of any license. It may be a genuine rarity at the edge of its range, or a stray, a released pet or an old misidentification, so treat it as unconfirmed.

These eight account for 75% of all licensed snake records in Utah; the most recorded, the western terrestrial garter snake, alone for 37%.

These eight account for 31% of all licensed spider records in Utah; the most recorded, the bold jumper, alone for 8%.

Observation records of venomous snakes in Utah run mostly May through October, peaking in May with 22% of them. December through February together hold under 2% of the records, so venomous snakes in Utah are rarely recorded in winter.

Observation records of spiders in Utah run mostly April through October, peaking in August with 21% of them. December through February together hold under 2% of the records, so spiders in Utah are rarely recorded in winter.

Observation records of scorpions in Utah run mostly March through September, peaking in August with 22% of them. December through February together hold under 2% of the records, so scorpions in Utah are rarely recorded in winter.

Washington County has the most records of venomous snakes in Utah, 94, most of them of the western rattlesnake. San Juan County and Salt Lake County follow.

Salt Lake County leads with 492 records (15%), followed by Washington County and Utah County; the top five counties hold 55% of the total. 29 of Utah's 29 counties have at least one licensed snake record.

Utah counties with their own page: Salt Lake County, Tooele County, Utah County and Washington County.

Yes. Utah has five venomous snake species on its list, the kind people usually call poisonous: western rattlesnake, prairie rattlesnake, sidewinder, Mohave rattlesnake and southwestern speckled rattlesnake. Strictly, snakes are venomous (they inject venom), not poisonous (harmful to eat or touch).

Yes. Five species are on the Utah list: the western rattlesnake, the prairie rattlesnake, the sidewinder, the Mohave rattlesnake and the southwestern speckled rattlesnake, with 546 licensed records between them. Most licensed records of the western rattlesnake come from Washington County, San Juan County and Salt Lake County.

No. GBIF holds no copperhead record for Utah under any license.

No. GBIF holds no cottonmouth record for Utah under any license.

No. GBIF holds no coral snake record for Utah under any license.

Utah has 427 licensed records of the western rattlesnake, which ranks the state 4th of the 9 states where it reaches our threshold. Its observation records in Utah run mostly May through September, peaking in May; most licensed records come from Washington County, San Juan County and Salt Lake County. Range in other states and photos: Western rattlesnake profile.

Utah has 102 licensed records of the prairie rattlesnake, which ranks the state 10th of the 14 states where it reaches our threshold. Most of its licensed records in Utah come from San Juan County, Grand County and Washington County. Range in other states and photos: Prairie rattlesnake profile.

Utah has 14 licensed records of the sidewinder, which ranks the state 4th of the 4 states where it reaches our threshold. Range in other states and photos: Sidewinder profile.

Utah has 2 licensed records of the Mohave rattlesnake, which ranks the state 6th of the 6 states where it reaches our threshold. Range in other states and photos: Mohave rattlesnake profile.

Utah has 1 licensed record of the southwestern speckled rattlesnake, which ranks the state 4th of the 4 states where it reaches our threshold. Range in other states and photos: Southwestern speckled rattlesnake profile.

Many snakes and spiders taken for venomous ones are harmless species with a similar look. These are the usual confusions, with each species' licensed records in Utah.

No copperheads reach the Utah list, and GBIF holds no copperhead record for Utah under any license, so a snake taken for one here is most likely a harmless lookalike. Those recorded in the state: eastern milksnake (22) and central plains milksnake (8).

Rattlesnakes: 546 licensed records in Utah. Harmless species often taken for them are also on the state list: gopher snake (505) and Great Plains rat snake (1). Together they have 506 licensed records, and the two sides are recorded about equally.

No coral snakes reach the Utah list, and GBIF holds no coral snake record for Utah under any license, so a snake taken for one here is most likely a harmless lookalike. Those recorded in the state: eastern milksnake (22), long-nosed snake (17), Sonoran mountain kingsnake (13) and central plains milksnake (8).

Widow spiders: 149 licensed records in Utah. Harmless species often taken for them are also on the state list: triangulate bud spider (40) and twospotted cobweb spider (7). Together they have 47 licensed records, and here the venomous species are the more recorded side, 3.2 to 1.

Recluse spiders are not on the Utah list, but they are recorded in Utah once (records of any license: desert recluse 1): treat any spider like this as venomous until identified. Harmless species often taken for them in the state: hobo spider (11), longbodied cellar spider (4) and spitting spider (2).

By count of venomous snake species, Utah ranks 12th of 50 states, level with 5 other states. Nationally, Arizona leads with 14 species; five list none.

Of the six states bordering Utah, Arizona, New Mexico and Nevada list more venomous snake species (Utah: 5 species; Arizona 14, New Mexico 10, Nevada 6, Colorado 3, Idaho 2, Wyoming 2).

Venomous snakes listed next door but not in Utah: the Arizona black rattlesnake (Arizona and New Mexico); the black-tailed rattlesnake (Arizona and New Mexico); the ridge-nosed rattlesnake (Arizona and New Mexico); the rock rattlesnake (Arizona and New Mexico); the Sonoran coralsnake (Arizona and New Mexico); the eastern black-tailed rattlesnake (New Mexico). Listed next door and recorded in Utah too, but too few times to list (records of any license): the western diamondback rattlesnake, recorded here only two times (listed in Arizona, Nevada and New Mexico); the western massasauga, recorded here only two times (listed in Arizona, Colorado and New Mexico). The most widely shared are the prairie rattlesnake and the western rattlesnake, each listed in five of the six bordering states.

Yes. One widow species is on the Utah list: the western black widow (149 records).

No. GBIF holds no brown recluse record for Utah under any license.

Utah has 149 licensed records of the western black widow, which ranks the state 5th of the 18 states where it reaches our threshold. Its observation records in Utah run mostly April through October, peaking in August; most licensed records come from Salt Lake County, Utah County and Grand County. Range in other states and photos: Western black widow profile.