Taxonomy
The following full taxonomy of the rattlesnakes (genera Crotalus and Sistrurus) includes the full list of species recognized as of 1982 (the most recent reference I own). I would appreciate any updates to this list. The list contains links to pictures and text information as available.
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Subclass: Diapsida
Order: Squamata
Suborder: Serpentes or Ophidia
Family: Viperidae
Subfamily: Crotalidae
Genus: Crotalus
Species:
C. adamanteus. Eastern Diamondback rattlesnake
GIF#2 Eastern diamondback
JPG Eastern diamondback
C. atrox. Western Diamondback rattlesnake
C. basilicus basilicus. Mexican west-coast rattlesnake
C. basilicus oaxacus. Oaxacan rattlesnake
C. catalinensis. Santa Catalina Island rattlesnake or rattleless rattlesnake
C. cerastes cerastes. Mojave Desert sidewinder
GIF Image - Two Eastern California sidewinders
C. cerastes cercobombus. Sonoran Desert sidewinder
C. cerastes latrorepens. Colorado Desert sidewinder
C. durissus durissus. Central American rattlesnake
C. durissus culminatus. Northwestern Neotropical rattlesnake
C. durissus terrificus. South American rattlesnake
C. durissus totonacus. Totonacan rattlesnake
C. durissus tzabcan. Yucatan Neotropical rattlesnake
C. enyo enyo. Lower California rattlesnake
C. enyo cerralvensis. Cerralvo Island rattlesnake
C. enyo furvus. Rosario rattlesnake
C. exsul. Cedros Island diamond rattlesnake
C. horridus horridus. Timber rattlesnake
C. horridus atricaudatus. Canebrake rattlesnake
C. intermedius intermedius. Totalcan small-headed rattlesnake
C. intermedius gloydi. Oaxacan small-headed rattlesnake
C. intermedius omiltemanus. Omilteman rattlesnake
C. lannomi. Autlan rattlesnake
C. lepidus lepidus. Mottled rock rattlesnake
C. lepidus klauberi. Banded rock rattlesnake
C. lepidus morulus. Tamaulipan rock rattlesnake
C. mitchellii mitchellii. San Lucan speckled rattlesnake
C. mitchellii angelensis. Angel de la Guarda Island speckled rattlesnake
C. mitchellii muertensis. El Muerto Island speckled rattlesnake
C. mitchellii pyrrhus. Southwestern speckled rattlesnake
C. mitchellii stephensi. Panamint rattlesnake
C. molossus molossus. Northern black-tailed rattlesnake
C. molossus estebanensis. San Esteban Island rattlesnake
C. molossus nigrescens. Mexican black-tailed rattlesnake
C. polystictus. Mexican lance-headed rattlesnake
C. pricei pricei. Western twin-spotted rattlesnake
C. pricei miquihuanas. Eastern twin-spotted rattlesnake
C. pusillus. Tancitaran dusky rattlesnake
C. ruber ruber. Red diamond rattlesnake
C. ruber lucasensis. San Lucan diamond rattlesnake
C. scutulatus scutulatus. Mojave rattlesnake
C. scutulatus salvini. Huamantlan rattlesnake
C. stejnegeri. Long-tailed rattlesnake
C. tigris. Tiger rattlesnake
C. tortugensis. Tortuga Island diamond rattlesnake
C. transversus. Cross-banded mountain rattlesnake
C. triseriatus triseriatus. Central-plateau dusky rattlesnake
C. trisereatus aquilus. Queretaran dusky rattlesnake
C. unicolor. Aruba Island rattlesnake
C. vegrandis. Uracoan rattlesnake
C. viridis viridis. Prairie rattlesnake
Western Rattler
C. viridis abyssus. Grand Canyon rattlesnake
C. viridis caliginis. Colorado Island rattlesnake
C. viridis cerberus. Arizona black rattlesnake
C. viridis concolor. Midget faded rattlesnake
C. viridis helleri. Southern Pacific rattlesnake
C. viridis lutosus. Great Basin rattlesnake
C. viridis nuntius. Hopi rattlesnake
C. viridis oreganus. Northern Pacific rattlesnake
C. willardi willardi. Arizona ridge-nosed rattlesnake
C. willardi amabilis. Del Nido ridge-nosed rattlesnake
C. willardi meridionalis. Southern ridge-nosed rattlesnake
C. willardi silus West Chihuahua ridge-nosed rattlesnake
Genus: Sistrurus
Species:
S. catenatus catenatus. Eastern massasauga
S. catenatus edwardsii. Desert massasauga
S. catenatus tergeminus. Western massasauga
S. miliarius miliarius. Carolina pygmy rattlesnake
S. miliarius barbouri. Dusky pygmy rattlesnake
S. miliarius streckeri. Western rattlesnake
S. ravus.Mexican pygmy rattlesnake