Crotalus viridis

Crotalus viridis
Hopi rattlesnake, C. v. nuntius
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Subfamily:	Crotalinae
Genus:	Crotalus
Species:	C. viridis
Binomial name
Crotalus viridis (Rafinesque, 1818)
Synonyms
Crotalinus viridis Rafinesque, 1818 Crotalurus viridis — Rafinesque, 1820 Crotalus confluentus Say In James, 1823 Crotalus Lecontei Hallowell, 1852 C[audisona]. confluenta — Cope, 1867 [Caudisona confluenta] Var. confluenta — Cope, 1867 [Caudisona confluenta] Var. lecontei — Cope, 1867 Crotalus confluentus var. pulverulentus Cope, 1883 Crotalus confluentus var. confluentus — Cope, 1883 Crotalus confluentus confluentus — Cope, 1892 Crotalus confluentus lecontei — Cope, 1892 Crotalus viridis viridis — Klauber, 1936

Crotalus viridis (Common names: prairie rattlesnake,western rattlesnake,Great Plains rattlesnake, and others) is a venomous pit viper species native to the western United States, southwestern Canada, and northern Mexico. Currently, two subspecies are recognized, including the nominate subspecies described here.

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 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.

They, and the subspecies mentioned below, 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 USA in eastern Oregon, eastern Washington, southern Idaho, most of Montana (where it is one of 10 snake species and the only venomous one), North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, Texas, New Mexico, extreme eastern Arizona, 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.

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Wikipedia