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Rattlesnake

Red Diamond Rattlesnake

Venomous

Crotalus ruber

Red Diamond Rattlesnake
Crotalus ruber, © Dee Shea Himes
Red Diamond RattlesnakeRed Diamond RattlesnakeRed Diamond RattlesnakeRed Diamond RattlesnakeRed Diamond Rattlesnake

6 photographs of the Red Diamond Rattlesnake. © Dee Shea Himes.

The Red Diamond Rattlesnake (Crotalus ruber) is a venomous snake in the Viperidae family, recorded in 2 countries.

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 Red Diamond Rattlesnake

Common names: red diamond rattlesnake, red rattlesnake, red diamond snake, more

Crotalus ruber is a venomous pit viper species found in southwestern California in the United States and Baja California in Mexico. Three subspecies are currently recognized, including the nominate subspecies described here.

Common names

Common names include: red diamond rattlesnake, red rattlesnake, red diamond snake, red diamond-backed rattlesnake, red rattler, and western diamond rattlesnake. The form found on Cedros Island, previously described as C. exsul, was referred to as the Cedros Island diamond rattlesnake, or Cedros Island rattlesnake.

Taxonomy

Not enough genetic and morphological diversity exists between C. exsul from Cedros Island and C. ruber from the mainland to warrant the recognition of both species. Since C. exsul Garman (1884) has priority over C. ruber Cope (1892), they suggested the island population be referred to as C. e. exsul and those from the mainland as C. e. ruber. In response, Smith et al. (1998) petitioned the ICZN to validate ruber over exsul in the interest of nomenclatural stability. In 2000, the ICZN published Opinion 1960 in which they ruled C. ruber should have precedence over C. exsul.

Hence, Crotalus ruber exsul, also known as the Cedros Island Rattlesnake, and native to Mexico is a subspecies of C. ruber.

Subspecies

C. r. exsul is thought to have separated from the mainland sister subspecies of C. ruber 210 thousand years ago.

Geographic range

Red diamond rattlesnakes are found in the United States in southwestern California and southward through the Baja California peninsula, although not in the desert east of the Sierra de Juárez in northeastern Baja California. It also inhabits a number of islands in the Gulf of California, including Angel de la Guarda, Pond, San Lorenzo del Sur, San Marcos, Danzante, Monserrate and San José. Off the west coast of Baja California, it is found on Isla de Santa Margarita, which is off Baja California Sur, and (as C. ruber exsul) on Isla de Cedros. Dwelling in brush covered hillsides, a favored habitat is the small caves and clefts of reddish sandstone mesas.

Description

This moderately large species commonly exceeds 100 cm (39 in) on the mainland. Large males may exceed 140 cm (55 in), although specimens of over 150 cm (59 in) are quite rare. The largest specimen on record measured 162 cm (64 in) (Klauber, 1937).

Crotalus ruber is very similar in pattern to C. atrox, but it is distinguished by its reddish color, to which the specific name, ruber, refers. Also, the first lower labial scale on each side is transversely divided to form a pair of anterior chin shields.

The dorsal scales are usually arranged in 29 rows, but may vary from 25 to 31 rows. Ventrals range from 185 to 206.

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Red Diamond Rattlesnake

Is the Red Diamond Rattlesnake venomous?
Yes. The Red Diamond Rattlesnake (Crotalus ruber) 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 Red Diamond Rattlesnake poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Red Diamond Rattlesnake is venomous, delivering venom through a bite.
Is the Red Diamond 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 Red Diamond Rattlesnake live?
The Red Diamond Rattlesnake has verified records in 2 countries, including United States of America, Mexico. See the distribution section below for its full range.
How do I identify the Red Diamond Rattlesnake?
Heavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
How big does the Red Diamond Rattlesnake get?
Typically 2–5 ft; some species exceed 6 ft.
What does the Red Diamond Rattlesnake eat?
This species preys on rabbits, ground squirrels, birds, lizards, and other snakes. Snakes from coastal populations consume prey of larger body mass than snakes from desert populations.
Why is it called the Red Diamond Rattlesnake?
Common names include: red diamond rattlesnake, red rattlesnake, red diamond snake, red diamond-backed rattlesnake, red rattler, and western diamond rattlesnake. The form found on Cedros Island, previously described as C. exsul, was referred to as the Cedros Island diamond rattlesnake, or Cedros Island rattlesnake.

If you are bitten by the Red Diamond 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

United States of AmericaMexico

By U.S. state

California

Snakes it is confused with

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 ruber

Keep learning

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