Red Diamond Rattlesnake

Appearance

This moderately large species commonly exceeds 100 cm on the mainland. Large males may exceed 140 cm , although specimens of over 150 cm are quite rare. The largest specimen on record measured 162 cm .

''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.

Snakes found in coastal regions are longer on average than those found in desert regions.

Naming

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....snipped...

Status

This species is classified as Least Concern on the IUCN Red List of Threatened Species . Species are listed as such due to their wide distribution, presumed large population, or because they are unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend was down when assessed in 2007.

Habitat

''C. ruber'' inhabits the cooler coastal zone, over the mountains, and into the desert beyond. It prefers the dense chaparral country of the foothills, cactus patches, and boulders covered with brush, from sea level to 1,500 m in altitude.

Reproduction

Mating occurs between February and April. Females give birth in August, to between three and 20 young. Neonates are 30 to 34 cm in length.

Food

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.

Defense

This species is of a mild disposition and has one of the least potent rattlesnake venoms. Nonetheless, a bite from this species is still a medical emergency and can be fatal without prompt antivenom treatment.

Brown lists an average venom yield of 364 mg and LD50 values of 4.0, 3.7 mg/kg IV, 6.0, 7.0, 6.7 mg/kg IP and 21.2 mg/kg SC for toxicity.

However, Norris warned this species has a relatively large venom yield containing high levels of proteolytic enzymes, especially in the adults. A publication he mentions by Rael ''et al.'' showed it contains at least three proteolytic hemorrhagins that degrade fibrinogen and cause myonecrosis, but no Mojave toxin. On the other hand, three specimens from Mexico studied by Glen ''et al.'' did have Mojave toxin and lacked hemorrhagic activity.

Bite symptoms include massive tissue swelling, pain, ecchymosis, hemorrhagic blebs, and necrosis. Systemic symptoms may include nausea, vomiting, coagulopathy, clinical bleeding and hemolysis.