Crotalus viridis | |
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Prairie rattlesnake, Crotalus v. viridis | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Suborder: | Serpentes |
Family: | Viperidae |
Genus: | Crotalus |
Species: | C. viridis |
Binomial name | |
Crotalus viridis (Rafinesque, 1818) | |
Synonyms | |
List
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Crotalus viridis (Common names: prairie rattlesnake, [3] [4] Great Plains rattlesnake, [5] ) is a venomous pit viper species native to the western United States, southwestern Canada, and northern Mexico. Currently, two subspecies are recognized, including the prairie rattlesnake (Crotalus viridis viridis), the nominate subspecies, and the Hopi rattlesnake ( Crotalus viridis nuntius ). [3]
The taxonomic history of this species is convoluted. Previously, seven other C. viridis subspecies were also recognized, including C. v. abyssus , C. v. caliginis , C. v. cerberus , C. v. concolor , C. v. helleri , C. v. lutosus and C. v. oreganus . However, in 2001 Ashton and de Queiroz described their analysis of the variation of mitochondrial DNA across the range of this species. Their results agreed broadly with those obtained by Pook et al. (2000). Two main clades were identified, east and west of the Rocky Mountains, which they argued were actually two different species: on the one hand C. viridis, including the conventional subspecies C. v. viridis and C. v. nuntius , and on the other C. oreganus , including all the other traditional subspecies of C. viridis. The authors retained the names of the traditional subspecies, but emphasized the need for more work to be done on the systematics of C. oreganus. [6] [7] [8]
This species commonly grows to more than 100 cm (3.3 ft) in length. The maximum recorded size is 151.5 cm (4.97 ft). In Montana, specimens occasionally exceed 120 centimetres (3.9 ft) in length; the species reaches its maximum size in this region. One of the most characteristic features is the presence of three or more, usually four, internasal scales. [6]
Identification characteristics will vary depending on which subspecies is encountered. Generally, prairie rattlesnakes are usually lightly colored in hues of brown. Patches of dark brown are often distributed in a dorsal pattern. A color band may be seen at the back of the eye. The prairie rattlesnake group carries the distinctive triangle-shaped head and pit sensory organs on either side of the head. A key characteristic that can help differentiate a prairie rattlesnake from other rattlesnakes is the presence of two internasals contacting the rostral. [9]
Prairie rattlesnakes are found in North America over much of the Great Plains, the eastern foothills and some intermontane valleys of the Rocky Mountains, from southwestern Canada through the United States to northern Mexico. In Canada, they occur in Alberta and Saskatchewan; in the US in eastern Idaho, most of Montana, North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, Texas, New Mexico, northeastern Arizona, extreme western Iowa, and in Mexico in northern Coahuila and northwestern Chihuahua. Its vertical range is from 100 m (330 ft) near the Rio Grande to over 2,775 m (9,104 ft) in elevation in Wyoming. [6]
Wright and Wright (1957) and Klauber (1997) both mention Utah as within the range of this species, including maps showing it confined to the extreme southeastern part of the state. [5] [10] The type locality is described as "the Upper Missouri [Valley, USA]". An emendation was proposed by H.M. Smith and Taylor (1950) to "Gross, Boyd County, Nebraska." [2]
Habitat characteristics can vary depending on subspecies and range. Generally, western rattlesnakes occupy areas with an abundant prey base. Many subspecies occupy somewhat rocky areas with outcrops serving as den sites. Prairie rattlesnakes have also been known to occupy burrows of other animals. [11] They seem to prefer dry areas with moderate vegetation coverage. Vegetation cover will vary depending on region and subspecies. [9]
Prairie rattlesnakes are primarily terrestrial, but occasionally climb in trees or bushes. Some even rest in crevices or caves. They are typically active diurnally in cooler weather and nocturnally during hot weather C. viridis. This species complex is equipped with powerful venom, using about 20-55 percent of venom in one bite, and will defend themselves if threatened or injured. As with other rattlesnake species, prairie rattlesnakes will rapidly vibrate their tails, which produces a unique rasping sound to warn intruders. [12] Prairie rattlesnakes prefer a straight migration path while migrating even in human-dominated environments because it leads to a higher chance of survival and better body condition throughout and after migration.
The venom of the Prairie rattlesnake is a complexly structured mixture of different proteins with enzymes such as proteases and peptidases found among them. [14] Besides the hemotoxin and its tissue destructive effect, the venom also has neurotoxic properties. [15]
Prairie rattlesnakes, because of their expansive distribution, have a wide array of prey. Generally, this species prefers small mammals, such as ground squirrels, ground nesting birds, mice, rats, small rabbits and prairie dogs. They will occasionally feed on amphibians and reptiles, and sometimes even other snakes. This is more commonly seen in juvenile snakes. [9]
Prairie rattlesnakes are viviparous and can produce from one to 25 young per reproduction event. The average number of young ranges from four to 12, but can vary greatly due to availability of food and environmental conditions. Males may compete for females during the breeding season, but western rattlesnake females may not necessarily breed every year. [16] They give birth in late summer or early fall, being their breed 22–28 cm long, without the need for parental care. In addition, the young are toxic as soon as they are born. They reach sexual maturity at three years of age. It is also common for females to give birth at communal den sites with the young born between August and October. [9] [12]
This species is classified as Least Concern on the IUCN Red List of Threatened Species (v3.1, 2001). 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 stable when assessed in 2006. [1]
Crotalus viridis nuntius Klauber, 1935, [3] the Hopi rattlesnake, inhabits the United States from northeastern and north-central Arizona, from the New Mexico border to Cataract Creek, including the Little Colorado River basin, the southern section of the Apache Indian Reservation, the Hopi Reservation, and the Coconino Plateau from the southern rim of the Grand Canyon to US Highway 66 in the south. [10]
Crotalus viridis viridis(Rafinesque, 1818), [3] the prairie rattlesnake, inhabits the North American Great Plains from the Rocky Mountains to 96° W and from southern Canada to extreme northern Mexico, including southwestern Saskatchewan, southeastern Alberta, eastern Washington, Idaho in the Lemhi Valley, Montana east of the higher Rockies, southwestern North Dakota, west, central and extreme southeastern South Dakota, western Iowa, central and western Nebraska, Wyoming except for the Rockies, Colorado, central and western Kansas, Oklahoma, extreme southeastern Utah, northeastern Arizona, New Mexico, western and southwestern Texas, northeastern Sonora, northern Chihuahua, northern Coahuila. [10]
Crotalus is a genus of venomous pit vipers, commonly known as rattlesnakes or rattlers, in the family Viperidae. The genus is found only in the Americas from southern Canada to northern Argentina. The generic name Crotalus is derived from the Greek word κρόταλονkrótalοn, which means "rattle" or "castanet", and refers to the rattle on the end of the tail, which makes this group so distinctive. As of July 2023, 44 to 53 species are recognized as valid.
Crotalus scutulatus is known commonly as the Mohave Rattlesnake. Other common English names include Mojave Rattlesnake and, referring specifically to the nominate (northern) subspecies: Northern Mohave Rattlesnake and Mojave Green Rattlesnake, the latter name undoubtedly acquiescing to the widely used colloquial name “Mojave green”. Campbell and Lamar (2004) supported the English name “Mohave (Mojave) rattlesnake” with some reluctance because so little of the snake’s range lies within the Mojave Desert.
The timber rattlesnake, canebrake rattlesnake, or banded rattlesnake is a species of pit viper endemic to eastern North America. Like all other pit vipers, it is venomous, with a very toxic bite. C. horridus is the only rattlesnake species in most of the populous Northeastern United States and is second only to its relatives to the west, the prairie rattlesnake, as the most northerly distributed venomous snake in North America. No subspecies are currently recognized.
Crotalus basiliscus, known as the Mexican west coast rattlesnake, Mexican green rattler, and also by other names, is a species of pit viper in the family Viperidae. The species is endemic to western Mexico. Like all other pit vipers, it is venomous. The specific name, basiliscus, is derived from the Greek word for king, βασιλισκος, and alludes to this snake's large size and potent venom. No subspecies are currently recognized.
Crotalus helleri or Crotalus oreganus helleri, also known commonly as the Southern Pacific rattlesnake, the black diamond rattlesnake, and by several other common names, is a pit viper species or subspecies found in southwestern California and south into Baja California, Mexico, that is known for its regional variety of dangerous venom types. It is sometimes considered a subspecies of Crotalus oreganus.
Crotalus willardi is a venomous pit viper species found in the southwestern United States and Mexico. This snake is found mainly in the "sky island" region. The IUCN reports this snake's conservation status as being of Least Concern. It is the official state reptile of Arizona.
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.
The western diamondback rattlesnake or Texas diamond-back is a rattlesnake species and member of the viper family, found in the southwestern United States and Mexico. Like all other rattlesnakes and all other vipers, it is venomous. It is likely responsible for the majority of snakebite fatalities in northern Mexico and the greatest number of snakebites in the U.S. No subspecies are currently recognized.
Crotalus mitchellii is a venomous pit viper species in the family Viperidae. The species is endemic to the Southwestern United States and adjacent northern Mexico. The species was named in honor of Silas Weir Mitchell (1829–1914), an American medical doctor who also studied rattlesnake venoms. Five subspecies are currently recognized, including the nominate subspecies described here.
Crotalus viridis nuntius is a venomous pit viper subspecies native primarily to the desert plateau of the northeastern portion of the American state of Arizona, but also ranges into northwestern New Mexico. Named for the Native American Hopi tribe, which inhabits the region, its range overlaps that of the nominate subspecies and some interbreeding is believed to occur. The taxonomy of the C. viridis group is a matter of debate, many considering the various subspecies to be nothing more than locality variations.
Crotalus oreganus abyssus is a venomous pit viper subspecies found only in the U.S. states of Arizona and Utah.
Crotalus durissus, known as the South American rattlesnake, tropical rattlesnake, and by other names, is a highly venomous pit viper species found in South America. It is the most widely distributed member of its genus. Currently, seven subspecies are recognized.
Crotalus simus is a venomous pit viper species found in Mexico and Central America. The specific epithet is Latin for "flat-nosed", likely because its head is blunt compared with lanceheads (Bothrops). Three subspecies are recognized, including the nominate subspecies described here.
Crotalus oreganus, commonly known as the Western rattlesnake or northern Pacific rattlesnake, is a venomous pit viper species found in western North America from the Baja California Peninsula to the southern interior of British Columbia.
The tiger rattlesnake is a highly venomous pit viper species found in the southwestern United States and northwestern Mexico. No subspecies are currently recognized. The specific name tigris,, refers to the many narrow dorsal crossbands, which create a pattern of vertical stripes when viewed from the side.
The Great Basin rattlesnake is a venomous pit viper species found in the Great Basin region of the United States.
Crotalus pricei is a species of venomous snake, a pit viper in the family Viperidae. The species is endemic to the southwestern United States and northern Mexico. Two subspecies are recognized.
Crotalus concolor, commonly known as the midget faded rattlesnake, faded rattlesnake, and yellow rattlesnake, is a pit viper species found in the western United States. It is a small rattlesnake known for its faded color pattern. Like all other pit vipers, it is venomous.
Crotalus cerberus is a venomous pit viper species found in the southwestern United States. It is known as the Arizona black rattlesnake, black rattlesnake, and several other common names.
Crotalus oreganus caliginis is a venomous pit viper subspecies endemic to South Coronado Island, Mexico.