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Rattlesnake

Tancitaran Dusky Rattlesnake

Venomous

Crotalus pusillus

Tancitaran Dusky Rattlesnake
Crotalus pusillus, no rights reserved

The Tancitaran Dusky Rattlesnake (Crotalus pusillus) is a venomous snake in the Viperidae family, recorded in 1 country.

If you are bitten

Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)

Also called
Rattlesnake
Family
Viperidae
Size
Typically 2–5 ft; some species exceed 6 ft.
Habitat
Deserts, rocky outcrops, grasslands, and woodland edges, depending on species.
Behavior
Ambush predators that buzz the tail as a warning; mostly active in warm months and often crepuscular in summer heat.
Identify
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Danger
high

About the Tancitaran Dusky Rattlesnake

Crotalus pusillus, or the Tancitaran Dusky Rattlesnake, is a venomous pit viper species found in west-central Mexico. No subspecies are currently recognized.

Description

Adult males may grow to more than 50 cm (20 in) in length, while females are smaller. The largest recorded length for a specimen was 68.2 cm (26.9 in).

Behavior

Campbell and Lamar (2004) found this species only to be active during the day. Within its range, night temperatures are low and seem to restrict its activity.

Geographic range

It is found in west-central Mexico in the Sierra de Coalcomán of southwestern Michoacán, the Transverse Volcanic Cordillera of west-central Michoacán, and in adjacent Jalisco. It is probably also found in northeastern Colima. Its type locality is reported as "Tancítaro, Michoacán, Mexico, altitude 5,000 ft" (5,000 ft = 1,524 m). It occurs at elevations between 1,525 and 2,380 metres (5,003 and 7,808 ft).

Conservation status

This species is classified as Endangered on the IUCN Red List of Threatened Species. The population trend was unknown when assessed in 2007.

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Tancitaran Dusky Rattlesnake

Is the Tancitaran Dusky Rattlesnake venomous?
Yes. The Tancitaran Dusky Rattlesnake (Crotalus pusillus) is venomous and belongs to the Viperidae family (rattlesnake). Its bite is considered high risk to people. Treat any bite as a medical emergency.
Is the Tancitaran Dusky Rattlesnake poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Tancitaran Dusky Rattlesnake is venomous, delivering venom through a bite.
Is the Tancitaran Dusky Rattlesnake dangerous?
Rattlesnake bites are medically serious. Expect intense pain, rapid swelling, and bruising. Stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to an emergency room immediately. Do NOT apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call Poison Control at 1-800-222-1222 or 911 in the US, or your local emergency number. (Source: CDC.)
Where does the Tancitaran Dusky Rattlesnake live?
The Tancitaran Dusky Rattlesnake has verified records in 1 country, including Mexico. See the distribution section below for its full range.
How do I identify the Tancitaran Dusky Rattlesnake?
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
How big does the Tancitaran Dusky Rattlesnake get?
Typically 2–5 ft; some species exceed 6 ft.

If you are bitten by the Tancitaran Dusky Rattlesnake

A venomous snakebite is a medical emergency. Call your local emergency number immediately. In the US, dial 911 or Poison Control at 1-800-222-1222.

Do

  • Get away from the snake and stay calm. Most bites worsen when people panic or try again to handle the snake.
  • Call 911 or Poison Control (1-800-222-1222) right away. Antivenom works best when given early.
  • Note the time of the bite and, from a safe distance, the snake's color and pattern, a phone photo is enough. Do not chase it.
  • Keep the bitten limb still and at roughly heart level. Sit or lie down and limit movement.
  • Remove rings, watches, and tight clothing near the bite before swelling starts.
  • Gently wash the bite with soap and water and cover it with a clean, dry dressing.

Do not

  • Do not cut the wound or try to suck out the venom.
  • Do not apply a tourniquet or ice.
  • Do not drink alcohol or caffeine.
  • Do not take aspirin or ibuprofen, they can worsen bleeding. Acetaminophen is safer for pain.
  • Do not try to catch or kill the snake. A dead snake can still bite by reflex.

First-aid guidance adapted from the U.S. Centers for Disease Control and Prevention (CDC NIOSH), Venomous Snakes. Educational only; always follow the instructions of emergency responders.

Where it is found

Mexico

More Viperidae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards
Squamata
FamilyA group of related snakes that share key traits
Viperidae
GenusA close-knit group of very similar species
Crotalus
SpeciesThis exact snake, named in the two-part scientific name
Crotalus pusillus

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.