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Citation: Midtgaard, Rune. RepFocus - A Survey of the Reptiles of the World. (www.repfocus.dk).
Latest update: August 27th, 2024.


Taxonomy of the family Viperidae
Bibliography of the genus Crotalus
Biodiversity of the family Viperidae








Genus
Crotalus

Typical Rattlesnakes

Klapperschlangen

Egentlige Klapperslanger

1758 Crotalus Linnaeus (type species: Crotalus horridus Linnaeus 1758)
Crotalinus Rafinesque 1815 [emendation of Crotalus; Klauber 1956 erroneously listed it as a new genus with type species Crotalinus cyanurus Rafinesque 1818]
1764 Crotalophorus Houttuyn (type species: Crotalus horridus Linnaeus 1758)
1768 Caudisona Laurenti (type species: Caudisona terrifica Laurenti 1768)
1820 Crotalurus Rafinesque [substitute name or emendation of Crotalinus Rafinesque 1815]
1830 Uropsophus Wagler (type species: Uropsophus triseriatus Wagler 1830)
1843 Urocrotalon Fitzinger (type species: Crotalus durissus Linnaeus 1758)
1867 Aploaspis Cope 1866 (type species: Caudisona lepida Kennicott 1861)
1875 Aechmophrys Coues in Wheeler (type species: Crotalus cerastes Hallowell 1854)
1884 Haploaspis Cope 1883 [emendation of Aploaspis Cope 1867]
1930 Paracrotalus Reuss (type species: Caudisona terrifica Laurenti 1768)
2009 Cottonus Hoser (type species: Crotalus intermedius Troschel 1865)
2009 Crutchfieldus Hoser (type species: Crotalus catalinensis Cliff 1954)
2009 Cummingea Hoser (type species: Crotalus stejnegeri Dunn 1919)
2009 Edwardsus Hoser (type species: Crotalus adamanteus Beauvois 1799)
2009 Hoserea Hoser (type species: Crotalus atrox Baird & Girard 1853)
2009 Matteoea Hoser (type species: Caudisona mitchellii Cope 1861)
2009 Mullinsus Hoser (type species: Crotalus adamanteus ruber Cope 1892)
2009 Piersonus Hoser (type species: Crotalus ravus Cope 1865)
2009 Pillotus Hoser (type species: Caudisona enyo Cope 1861)
2009 Sayersus Hoser (type species: Crotalinus viridis Rafinesque 1818)
2009 Smythus Hoser (type species: Crotalus molossus Baird & Girard 1853)
Contents: 59 species, of which 41 (69.5%) are endemic.
Endemism: 0% 100%
Remarks: Hoser (2009b) revalidated Aechmophrys, Caudisona, and Urosophus as separate genera and described four new genera and seven new subgenera. His publication has generally been ignored, as it is herein, and some authors have recommended not to use his taxonomy (e.g., Zaher, Grazziotin, Cadle, Murphy, Moura-Leite & Bonatto 2009; Wüster & Bernils 2011). A case is pending before the International Committee on Zoological Nomenclature regarding the validity of Hoser's works.
Distribution: North America, Central America, South America.
Reported from: Argentina, Aruba, Belize, Bolivia, Brazil (Alagoas, Amapa, Amazonas, Bahia, Ceara, Distrito Federal, Goias, Maranhao, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Para [incl. Marajo Island], Paraiba, Parana, Pernambuco, Piaui, Rio de Janeiro, Rio Grande do Norte, Rio Grande do Sul, Rondonia, Roraima, Santa Catarina, Sao Paulo, Sergipe, Tocantins), Canada (Alberta, British Columbia, Saskatchewan), Colombia, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Mexico (Aguascalientes, Baja California Norte [incl. Isla Angel de la Guarda, Isla Cedros, Isla San Lorenzo Sur, Islas Coronados (incl. Isla Coronado Sur), Islas Las Encantadas [incl. Isla El Muerto], Baja California Sur [incl. Isla Carmen, Isla Cerralvo, Isla San Francisco, Isla San Jose, Isla San Marcos, Isla Santa Catalina, Isla Tortuga], Campeche, Chiapas, Chihuahua, Coahuila, Colima, Distrito Federal, Durango, Guanajuato, Guerrero, Hidalgo, Jalisco, Mexico State, Michoacan, Morelos, Nayarit, Nuevo Leon, Oaxaca, Puebla, Queretaro, Quintana Roo, San Luis Potosi, Sinaloa, Sonora [incl. Isla San Esteban, Isla San Pedro Martir], Tabasco, Tamaulipas, Tlaxcala, Veracruz, Yucatan, Zacatecas), Nicaragua, Paraguay, Peru, Surinam, Uruguay, USA (Alabama, Arizona, Arkansas, California [incl. Channel Islands], Colorado, Connecticut, Florida, Georgia, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming), Venezuela (incl. Margarita).

Crotalus abyssus

Grand Canyon Rattlesnake

Grand-Canyon-Klapperschlange

Grand Canyon-klapperslange

1930 Crotalus confluentus abyssus Klauber
Crotalus viridis abyssus Klauber 1936
Crotalus abyssus Douglas, Douglas, Schuett, Porras & Holycross 2002
Crotalus oreganus abyssus Ashton & Queiroz 2001

Remarks: Previously treated as a subspecies of viridis or, more recently, of oreganus. Revalidated by Douglas, Douglas, Schuett, Porras & Holycross (2002), followed by other works (e.g., Wallach, Williams & Boundy 2014). However, Davis, Douglas, Collyer & Douglas (2016) recommended treating abyssus as part of lutosus.
Distribution: USA (Arizona, Utah).


Crotalus abyssus
© Rune Midtgaard

Crotalus adamanteus

Eastern Diamondback Rattlesnake

Östliche Diamantklapperschlange

Østlig Diamantklapperslange

1799 Crotalus adamanteus Beauvois
Caudisona adamantea Cope 1867
1801 Crotalus rhombifer Latreille in Sonnini & Latreille [1801-02] (Campbell & Lamar 2004)
1954 Crotalus adamanteus pleistofloridensis Brattstrom (Campbell & Lamar 2004)
1954 Crotalus giganteus Brattstrom (Campbell & Lamar 2004)

Distribution: USA (Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina).


Crotalus adamanteus
© Rune Midtgaard

Crotalus angelensis

Angel de la Guarda Island Speckled Rattlesnake

Angel de la Guarda-Klapperschlange

Angel de la Guarda-klapperslange

1963 Crotalus mitchelli angelensis Klauber
Crotalus angelensis Grismer 1999

Remarks: Previously regarded as a subspecies of mitchellii. Treated as a separate species herein, following Grismer (1999) and several subsequent works (e.g., Liner 2007; Enderson, Quijada-Mascarenas, Turner, Rosen & Bezy 2009; Meik, Streicher, Lawing, Flores-Villela & Fujita 2015; Meik, Streicher, Lawing, Flores-Villela & Fujita 2015). Regarded as a synonym of mitchellii by other authors (e.g., Wallach, Williams & Boundy 2014; Campbell & Lamar 2004).
Distribution: Mexico (Baja California Norte: Isla Angel de la Guarda).


Crotalus aquilus

Queretaran Dusky Rattlesnake, Queretaran Blotched Rattlesnake

Queretaro-Plateau-Klapperschlange

Queretaro-klapperslange

1952 Crotalus triseriatus aquilus Klauber
Crotalus aquilus Harris 1978
1978 Crotalus triseriatus quadrangularis Harris & Smith (Campbell & Lamar 2004)

Other common names:
quadrangularis: Hidalgan Dusky Rattlesnake
Remarks: Previously regarded as a subspecies of triseriatus. Revalidated by Dorcas (1992).
Distribution: Mexico (Aguascalientes, Distrito Federal, Guanajuato, Hidalgo, Jalisco, Mexico State, Michoacan, Queretaro, San Luis Potosi, Veracruz, Zacatecas).


Crotalus aquilus
© Rune Midtgaard

Crotalus armstrongi

Western Dusky Rattlesnake, (Armstrong's Dusky Rattlesnake)

Westliche Plateau-Klapperschlange

Vestlig Mørk Klapperslange

1978 Crotalus triseriatus armstrongi Campbell
Crotalus armstrongi Reyes-Velasco, Meik, Smith & Castoe 2013

Remarks: Previously included the population now assigned to campbelli. Listed as likely to occur in Colima by Lemos-Espinal, Smith, Pierce & Painter (2020), although recorded already by Reyes-Velasco, Hermosillo-Lopez, Grünwald & Avila-Lopez (2009).
Distribution: Mexico (Colima, Jalisco, Michoacan, Nayarit).


Crotalus atrox

Western Diamondback Rattlesnake

Westliche Diamantklapperschlange, Texas-Klapperschlange

Vestlig Diamantklapperslange, Texas-klapperslange

1852 Crotalus cinereous Le Conte in Hallowell [suppressed] (International Commission on Zoological Nomenclature 1955; Campbell & Lamar 2004)
1853 Crotalus atrox Baird & Girard
Crotalus adamanteus atrox Jan 1859
1861 Crotalus atrox var. sonoraensis Kennicott (Campbell & Lamar 2004)
Crotalus adamanteus var. sonoriensis Jan 1863 [unjustified emendation]
Crotalus sonoriensis Golay & al. 1993 [cited in the synonymy of atrox]

Remarks: Previously included tortugensis. Recorded from several places in Kansas, where it may have been introduced, and although at least one of the records may represent a reproducing population, presence in the state needs confirmation (Campbell & Lamar 2004). Reports from Missouri are questionable (Campbell & Lamar 2004). Also older, isolated records from Oaxaca (Mexico), where it may be extirpated.
Distribution: Mexico (Aguascalientes, Baja California Norte, Baja California Sur, Chihuahua, Coahuila, Durango, Guanajuato, Hidalgo, Jalisco, Mexico State, Nuevo Leon, Oaxaca, Queretaro, San Luis Potosi, Sinaloa, Sonora [incl. Isla San Pedro Martir], Tamaulipas, Veracruz, Zacatecas), USA (Arizona, Arkansas, California, Nevada, New Mexico, Oklahoma, Texas).


Crotalus atrox
© Rune Midtgaard

Crotalus basiliscus

Mexican West Coast Rattlesnake, Mexican Green Rattlesnake

Mexikanische Westküsten-Klapperschlange, Basilisken-Klapperschlange

Vestmexicansk Klapperslange

1864 Caudisona basilisca Cope
Crotalus basiliscus Cope 1875
Crotalus durissus basiliscus Garman 1884
Crotalus terrificus basiliscus Amaral 1929

Remarks: Previously included totonacus and the subspecies oaxacus, now considered a subspecies of molossus.
Distribution: Mexico (Aguascalientes, Chihuahua, Colima, Jalisco, Michoacan, Nayarit, Sinaloa, Sonora, Zacatecas).


Crotalus basiliscus
© Rune Midtgaard

Crotalus brunneus

Oaxacan Pygmy Rattlesnake

Oaxaca-Zwergklapperschlange

Oaxaca-dværgklapperslange

1978 Sistrurus ravus brunneus Harris & Simmons
Crotalus ravus brunneus Bryson 2007
Crotalus brunneus Blair, Bryson, Linkem, Lazcano, Klicka & McCormack 2018

Distribution: Mexico (Oaxaca).





Crotalus caliginis

Coronado Sur Island Rattlesnake

Coronado-Klapperschlange

Coronado-klapperslange

1949 Crotalus viridis caliginis Klauber
Crotalus caliginis Grismer 2001
Crotalus oreganus caliginis Ashton & Queiroz 2001

Remarks: Previously regarded as a subspecies or synonym of viridis (e.g., Golay & al. 1993; Liner 1994), of helleri (e.g., Schuett, Porras & Holycross 2002; Ashton & Queiroz 2001; Flores-Villela & Marquez 2004) or of oreganus (e.g., Campbell & Lamar 2004). It is here treated as a separate species, following several recent works (e.g., Grismer 2001; Liner 2007; Enderson, Quijada-Mascarenas, Turner, Rosen & Bezy 2009; Wallach, Williams & Boundy 2014). However, Davis, Douglas, Collyer & Douglas (2016) recommended treating caliginis as an insular population of helleri.
Distribution: Mexico (Baja California Norte: Islas Coronados: Isla Coronado Sur).


Crotalus campbelli

Guerreran Dusky Rattlesnake

Guerrero-Plateau-Klapperschlange

Mørk Guerrero-klapperslange

2014 Crotalus campbelli Bryson, Linkem, Dorcas, Lathrop, Jones, Alvarado-Díaz, Grünwald & Murphy

Remarks: Previously regarded as a population of triseriatus (e.g., Boulenger 1896) or of armstrongi (e.g., Dorcas 1992).
Distribution: Mexico (Colima, Jalisco, Nayarit).


Crotalus catalinensis

Santa Catalina Rattlesnake, Santa Catalina Island Rattleless Rattlesnake

Santa Catalina-Klapperschlange

Santa Catalina-klapperslange

1954 Crotalus catalinensis Cliff

Distribution: Mexico (Baja California Sur: Isla Santa Catalina).


Crotalus catalinensis
© Rune Midtgaard

Crotalus cerastes

Sidewinder

Seitenwinder-Klapperschlange, Gehörnte Klapperschlange

Sideruller

1854 Crotalus cerastes Hallowell
Caudisona cerastes Cope 1867
Aechmophrys cerastes Coues 1875
1944 Crotalus cerastes laterorepens Klauber
1953 Crotalus cerastes cercobombus Savage & Cliff

Other common names:
cerastes: Mojave Desert Sidewinder
cercobombus: Sonora Desert Sidewinder
laterorepens: Colorado Desert Sidewinder
Distribution: Mexico (Baja California Norte, Sonora), USA (Arizona, California, Nevada, Utah).


Crotalus cerastes
© Rune Midtgaard

Crotalus cerberus

Arizona Black Rattlesnake

Schwarze Klapperschlange

Sort Klapperslange

1875 Caudisona lucifer cerberus Coues
Crotalus oregonus cerberus [sic] Garman 1884
Crotalus viridis cerberus Klauber 1949
Crotalus oreganus cerberus Ashton & Queiroz 2001
Crotalus cerberus Douglas, Douglas, Schuett, Porras & Holycross 2002

Remarks: Regarded as a separate species by many authors (e.g., Douglas, Douglas, Schuett, Porras & Holycross 2002; Brennan & Holycross 2006; Crother (ed.) 2008, 2012; Enderson, Quijada-Mascarenas, Turner, Rosen & Bezy 2009), but retained as a subspecies of oreganus by others (e.g., Crother, Boundy & al. 2003; Campbell & Lamar 2004). Validity as a separate species supported by Davis, Douglas, Collyer & Douglas (2016).
Introduced to: USA (Iowa).
Distribution: USA (Arizona, New Mexico).


Crotalus cerberus
© Rune Midtgaard

Crotalus concolor

Midget Faded Rattlesnake

Utah-Klapperschlange

Utah-klapperslange

1929 Crotalus concolor Woodbury [not Crotalus durissus var. concolor Jan 1859]
Crotalus confluentus concolor Woodbury 1930
Crotalus viridis concolor Klauber 1936
Crotalus oreganus concolor Ashton & Queiroz 2001

Remarks: Previously treated as a subspecies of viridis or, more recently, oreganus. Revalidated as a separate species by Douglas, Douglas, Schuett, Porras & Holycross (2002), followed by others (e.g., Wallach, Williams & Boundy 2014). Validity as a separate species supported by Davis, Douglas, Collyer & Douglas (2016).
Distribution: USA (Arizona, Colorado, Utah, Wyoming).


Crotalus concolor
© Rune Midtgaard

Crotalus culminatus

Northwestern Neotropical Rattlesnake, Northwestern Middle American Rattlesnake

Nordwestliche Neotropische Klapperschlange

Nordvestlig Neotropisk Klapperslange

1952 Crotalus durissus culminatus Klauber
Crotalus simus culminatus Campbell & Lamar 2004
Crotalus culminatus Wüster, Ferguson, Quijada-Mascareñas, Pook, Graca-Salomão & Thorpe 2005

Remarks: Reyes Velasco, Cox, Jones, Borja & Campbell (2022) presented evidence suggesting that ehecatl may be a synonym of culminatus.
Distribution: Mexico (Guerrero, Mexico State, Michoacan, Morelos, Puebla).


Crotalus culminatus
© Rune Midtgaard

Crotalus durissus

South American Rattlesnake, Neotropical Rattlesnake

Tropische Klapperschlange, Rautenklapperschlange, Schauer-Klapperschlange, Cascabel

Sydamerikansk Klapperslange

1758 Crotalus Durissus Linnaeus
Urocrotalon durissus Fitzinger 1843
Crotalus terrificus durissus Amaral 1929
1758 Crotalus Dryinas Linnaeus [suppressed by Principle of the First Revisor (Art. 24)] (Campbell & Lamar 2004)
Crotalus strepitans dryinas Daudin 1803
Crotalus durissus dryinus Hoge 1966
1768 Caudisona Gronovii Laurenti (Campbell & Lamar 2004)
1768 Caudisona orientalis Laurenti (Campbell & Lamar 2004)
Crotalus orientalis Gmelin 1788
1768 Caudisona terrifica Laurenti
Crotalus terrificus Cope 1875
Crotalus durissus terrificus Klauber 1936
Paracrotalus terrificus Reuss 1930
1778 Crotalus exalbidus Boddaert (Campbell & Lamar 2004)
1801 Crotalus immaculatus Latreille in Sonnini & Latreille (Campbell & Lamar 2004)
1803 Crotalus strepitans Daudin (Campbell & Lamar 2004)
1813 Crotalus loeflingii Humboldt in Humboldt & Bonpland (Campbell & Lamar 2004)
1824 Crotalus cascavella Wagler (Wüster, Ferguson, Quijada-Mascareñas, Pook, Graca-Salomão & Thorpe 2005; Campbell & Lamar 2004)
Crotalus durissus cascavella Hoge 1966
1833 Crotalus cumanensis Humboldt
Crotalus durissus cumanensis Hoge 1966
1905 Crotalus pulvis Ditmars "1904" (status uncertain; Campbell & Lamar 2004)
1926 Crotalus terrificus var. collilineatus Amaral (Wüster, Ferguson, Quijada-Mascareñas, Pook, Graca-Salomão & Thorpe 2005; Campbell & Lamar 2004)
Crotalus durissus collilineatus Hoge 1966
1926 Crotalus terrificus var. collirhombeatus Amaral (Campbell & Lamar 2004)
1956 Crotalus durissus crotaminicus Moura Goncalves [nomen nudum] (Klauber 1972; Campbell & Lamar 2004)
1966 Crotalus durissus marajoensis Hoge "1965"
1966 Crotalus durissus ruruima Hoge "1965"
Crotalus territicus ruruima Sandner-Montilla 1980
1978 Crotalus durissus trigonicus Harris & Simmons "1976-77"
1980 Crotalus pifanorum Sandner-Montilla (status uncertain; McCranie 1993; Campbell & Lamar 2004)
Crotalus durissus pifanorum Campbell & Lamar 2004
1995 Crotalus maricelae Garcia-Perez (status uncertain; Campbell & Lamar 2004)

Other common names:
cascavella: Northeastern Brazilian Rattlesnake
collilineatus: Central Brazilian Rattlesnake
cumanensis: Venezuelan Rattlesnake
dryinus: Amazonian Rattlesnake, Guianan Rattlesnake
durissus: Central American Rattlesnake
marajoensis: Marajo Island Rattlesnake, Marajoan Rattlesnake
ruruima: Mount Roraima Rattlesnake
terrificus: South American Rattlesnake, Tropical Rattlesnake
trigonicus: Rupununi Savanna Rattlesnake
Remarks: Now restricted to South America. Previously included culminatus, simus, totonacus, tzabcan, unicolor, and vegrandis. The two latter forms are still sometimes regarded as subspecies of durissus (e.g., Campbell & Lamar 2004). Records from Mexico and Central America refer to the first four species.
Distribution: Argentina, Bolivia, Brazil (Alagoas, Amapa, Amazonas, Bahia, Ceara, Distrito Federal, Goias, Maranhao, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Para [incl. Marajo Island], Paraiba, Parana, Pernambuco, Piaui, Rio de Janeiro, Rio Grande do Norte, Rio Grande do Sul, Rondonia, Roraima, Santa Catarina, Sao Paulo, Sergipe, Tocantins), Colombia, French Guiana, Guyana, Paraguay, Peru, Surinam, Uruguay, Venezuela (incl. Isla Margarita).


Crotalus durissus
© Rune Midtgaard

Crotalus ehecatl

Chiapas Rattlesnake

Chiapas-Klapperschlange

Chiapas-klapperslange

2020 Crotalus ehecatl Carbajal-Márquez, Cedeño-Vázquez, Martínez-Arce, Neri-Castro & Machkour-M'Rabet

Remarks: Suggested to be a synonym of culminatus by Reyes Velasco, Cox, Jones, Borja & Campbell (2022).
Distribution: Mexico (Chiapas, Oaxaca).





Crotalus enyo

Baja California Rattlesnake

Niederkalifornische Klapperschlange

Baja California-klapperslange

1861 Caudisona enyo Cope
Crotalus enyo Cope 1875
Crotalus oregonus enyo Garman 1884
Crotalus confluentus enyo Amaral 1929
1954 Crotalus enyo cerralvensis Cliff
1954 Crotalus enyo furvus Lowe & Norris

Other common names:
cerralvensis: Cerralvo Island Rattlesnake
enyo: Lower California Rattlesnake
furvus: Rosario Rattlesnake
Distribution: Mexico (Baja California Norte [incl. Islas Coronados], Baja California Sur [incl. Isla Carmen, Isla Cerralvo, Isla San Francisco, Isla San Jose]).


Crotalus enyo
© Rune Midtgaard

Crotalus ericsmithi

Southern Long-tailed Rattlesnake, Guerreran Long-tailed Rattlesnake

Südliche Langschwanz-Klapperschlange

Sydlig Langhalet Klapperslange

2008 Crotalus ericsmithi Campbell & Flores-Villela

Distribution: Mexico (Guerrero).


Crotalus estebanensis

San Esteban Island Black-tailed Rattlesnake

San Esteban-Klapperschlange

San Esteban-klapperslange

1949 Crotalus molossus estebanensis Klauber
Crotalus estebanensis Grismer 1999

Remarks: Previously regarded as a subspecies of molossus. Treated as a separate species here, following Grismer (1999) and several subsequent works (e.g., Liner 2007; Enderson, Quijada-Mascarenas, Turner, Rosen & Bezy 2009).
Distribution: Mexico (Sonora: Isla San Esteban).


Crotalus exiguus

Guerreran Pygmy Rattlesnake

Guerrero-Zwergklapperschlange

Guerrero-dværgklapperslange

1979 Sistrurus ravus exiguus Campbell & Armstrong
Crotalus ravus exiguus Bryson 2007
Crotalus exiguus Blair, Bryson, Linkem, Lazcano, Klicka & McCormack 2018

Distribution: Mexico (Guerrero).





Crotalus helleri

Southern Pacific Rattlesnake

Südliche Pazifik-Klapperschlange

Sydvestlig Klapperslange

1905 Crotalus helleri Meek
Crotalus viridis helleri Klauber 1949
Crotalus oreganus helleri Ashton & Queiroz 2001

Remarks: Previously treated as a subspecies of viridis or, more recently, oreganus. Revalidated as a separate species by Douglas, Douglas, Schuett, Porras & Holycross (2002), followed by several other works (e.g., Wallach, Williams & Boundy 2014). Validity as a separate species supported by Davis, Douglas, Collyer & Douglas (2016). See remarks under caliginis.
Distribution: Mexico (Baja California Norte, Baja California Sur), USA (California [incl. Channel Islands]).


Crotalus helleri
© Rune Midtgaard

Crotalus horridus

Timber Rattlesnake

Wald-Klapperschlange

Skovklapperslange

1758 Crotalus horridus Linnaeus
Caudisona horrida Fleming 1822
1789 Crotalus boiquira Lacepede "1788-89" (International Commission on Zoological Nomenclature 1987 (Opinion 1463); Campbell & Lamar 2004)
1801 Crotalus atricaudatus Latreille in Sonnini & Latreille (Clark, Moler, Possardt, Savitzky, Brown & Bowen 2003; Campbell & Lamar 2004)
Crotalus horridus atricaudatus Garman 1884
1805 Crotalus zetazomae Brickell (Campbell & Lamar 2004)
1818 Crotalinus cyanurus Rafinesque (Campbell & Lamar 2004)
Crotalurus cyanurus Rafinesque 1820
1820 Crotalus catesbaei Hemprich (Campbell & Lamar 2004)
1859 Crotalus durissus var. concolor Jan [suppressed; not Crotalus concolor Woodbury 1929] (International Commission on Zoological Nomenclature 1955 (Opinion 339); Campbell & Lamar 2004)
1859 Crotalus durissus var. melanurus Jan (Campbell & Lamar 2004)
1863 Crotalus durissus var. mexicana Jan (Campbell & Lamar 2004)
1873 Crotalus fasciatus Higgins (Campbell & Lamar 2004)

Other common names:
atricaudatus: Canebrake Rattlesnake
Remarks: Presumably extinct in Ontario (Canada), since last report was in 1941 (Cook 1984). Previously known from Rhode Island, but may be extirpated, since there are no recent reports from the state (Klemens 1993). There are undocumented reports from Delaware, but even if true, the species is presumably extirpated from the entire Delmarva Peninsula (White & White 2002).
Extinct in: Canada (Ontario), USA (Maine, Rhode Island).
Distribution: USA (Alabama, Arkansas, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Nebraska, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas, Vermont, Virginia, West Virginia, Wisconsin).


Crotalus horridus
© Rune Midtgaard

Crotalus intermedius

Mexican Small-headed Rattlesnake

Kleinkopf-Klapperschlange

Mexicansk Smalhovedet Klapperslange

1865 Crotalus intermedius Troschel in Müller
Sistrurus intermedius Garman 1884
1895 Crotalus omiltemanus Gunther
Crotalus intermedius omiltemanus Klauber 1952
1941 Crotalus triseriatus gloydi Taylor
Crotalus gloydi Smith & Taylor 1945
Crotalus intermedius gloydi Davis & Dixon 1957
1946 Crotalus gloydi lautus Smith (Campbell & Lamar 2004)

Other common names:
gloydi: Oaxacan Small-headed Rattlesnake
intermedius: Totalcan Small-headed Rattlesnake
omiltemanus: Omilteman Small-headed Rattlesnake
Distribution: Mexico (Guerrero, Hidalgo, Oaxaca, Puebla, Tlaxcala, Veracruz).


Crotalus lannomi

Autlán Rattlesnake

Autlán-Klapperschlange

Autlán-klapperslange

1966 Crotalus lannomi Tanner

Distribution: Mexico (Colima, Jalisco).


Crotalus lepidus

Common Rock Rattlesnake

Gewöhnliche Felsen-Klapperschlange

Almindelig Bjergklapperslange

1861 Caudisona lepida Kennicott
Aploaspis lepida Cope 1867
Crotalus lepidus Cope 1884
1887 Crotalus tigris var. palmeri Garman (Campbell & Lamar 2004)
Crotalus palmeri Günther 1895
1936 Crotalus lepidus klauberi Gloyd
1944 Crotalus semicornutus Taylor (Campbell & Lamar 2004)
1972 Crotalus lepidus maculosus Tanner, Dixon & Harris
1978 Crotalus lepidus castaneus Juliá-Zertuche & Treviño

Other common names:
klauberi: Banded Rock Rattlesnake
lepidus: Mottled Rock Rattlesnake
maculosus: Durangan Rock Rattlesnake
Remarks: Previously included morulus.
Distribution: Mexico (Aguascalientes, Chihuahua, Coahuila, Durango, Jalisco, Nayarit, Nuevo Leon, San Luis Potosi, Sinaloa, Sonora, Zacatecas), USA (Arizona, New Mexico, Texas).


Crotalus lepidus
© Rune Midtgaard

Crotalus lorenzoensis

San Lorenzo Sur Island Red Diamond Rattlesnake

San Lorenzo-Klapperschlange

San Lorenzo-klapperslange

1975 Crotalus ruber lorenzoensis Radcliffe & Maslin
Crotalus exsul lorenzoensis Grismer, McGuire & Hollingsworth 1994
Crotalus lorenzoensis Grismer 1999

Remarks: Previously regarded as a subspecies of ruber. Treated as a separate species here, following Grismer (1999) and several subsequent works (e.g., Liner 2007; Enderson, Quijada-Mascarenas, Turner, Rosen & Bezy 2009). Regarded as a synonym of ruber by Wallach, Williams & Boundy (2014).
Distribution: Mexico (Baja California Norte: Isla San Lorenzo Sur).


Crotalus lutosus

Great Basin Rattlesnake

Great-Basin-Klapperschlange

Great Basin-klapperslange

1930 Crotalus confluentus lutosus Klauber
Crotalus viridis lutosus Klauber 1936
Crotalus oreganus lutosus Ashton & Queiroz 2001
Crotalus lutosus Arizona Game and Fish Department 2002

Remarks: Previously treated as a subspecies of viridis or, more recently, oreganus. Regarded as a separate species by Douglas, Douglas, Schuett, Porras & Holycross (2002) and several other works (e.g., Wallach, Williams & Boundy 2014). Validity as a separate species supported by Davis, Douglas, Collyer & Douglas (2016). See remarks under abyssus.
Distribution: USA (Arizona, California, Idaho, Nevada, Oregon, Utah).


Crotalus lutosus
© Rune Midtgaard

Crotalus mictlantecuhtli

Veracruz Rattlesnake

Veracruz-Klapperschlange

Veracruz-klapperslange

2020 Crotalus mictlantecuhtli Carbajal-Márquez, Cedeño-Vázquez, Martínez-Arce, Neri-Castro & Machkour-M'Rabet

Distribution: Mexico (Veracruz).





Crotalus mitchellii

San Lucan Speckled Rattlesnake, (Speckled Rattlesnake)

San-Lucas-Klapperschlange

San Lucas-klapperslange

1861 Caudisona mitchellii Cope
Crotalus mitchellii Cope 1875
Crotalus oregonus mitchellii Garman 1884
Crotalus tigris mitchellii Amaral 1929
Crotalus confluentus mitchellii Klauber 1930
1922 Crotalus goldmani Schmidt (Campbell & Lamar 2004)

Remarks: Now restricted to Mexico. Previously included angelensis, muertensis, pyrrhus, and stephensi. Records from USA, Sonora, and most of Baja California Norte refer to pyrrhus and stephensi.
Distribution: Mexico (Baja California Norte, Baja California Sur [incl. Isla Carmen, Isla Cerralvo, Isla San Jose]).


Crotalus molossus

Western Black-tailed Rattlesnake

Westliche Schwarzschwanz-Klapperschlange

Vestlig Sorthalet Klapperslange

1853 Crotalus molossus Baird & Girard
Caudisona molossus Cope 1860
Crotalus durissus molossus Garman 1884
1936 Crotalus molossus nigrescens Gloyd
1948 Crotalus basiliscus oaxacus Gloyd
Crotalus molossus oaxacus Campbell & Lamar 1989

Other common names:
molossus: Northern Black-tailed Rattlesnake
nigrescens: Mexican Black-tailed Rattlesnake
oaxacus: Oaxacan Black-tailed Rattlesnake
Remarks: Previously included estebanensis and ornatus. The Oaxacan Black-tailed Rattlesnake (oaxacus) was previously regarded as a subspecies of basiliscus.
Distribution: Mexico (Aguascalientes, Chihuahua, Coahuila, Distrito Federal, Durango, Guanajuato, Hidalgo, Jalisco, Mexico State, Michoacan, Morelos, Nayarit, Nuevo Leon, Oaxaca, Puebla, Queretaro, San Luis Potosi, Sinaloa, Sonora, Tamaulipas, Tlaxcala, Veracruz, Zacatecas), USA (Arizona, New Mexico).


Crotalus molossus
© Rune Midtgaard

Crotalus morulus

Tamaulipan Rock Rattlesnake

Tamaulipas-Felsen-Klapperschlange

Tamaulipas-bjergklapperslange

1952 Crotalus lepidus morulus Klauber
Crotalus morulus Bryson, Linkem, Dorcas, Lathrop, Jones, Alvarado-Díaz, Grünwald & Murphy 2014

Distribution: Mexico (Coahuila, Nuevo Leon, Tamaulipas).


Crotalus muertensis

El Muerto Island Speckled Rattlesnake

El Muerto-Klapperschlange

El Muerto-klapperslange

1949 Crotalus mitchelli muertensis Klauber
Crotalus muertensis Grismer 1999

Remarks: Previously regarded as a subspecies of mitchelli. Treated as a separate species here, following Grismer (1999) and several subsequent works (e.g., Liner 2007; Enderson, Quijada-Mascarenas, Turner, Rosen & Bezy 2009). Regarded as a synonym of mitchelli by some authors (e.g., Campbell & Lamar 2004; Wallach, Williams & Boundy 2014; Meik, Streicher, Lawing, Flores-Villela & Fujita 2015).
Distribution: Mexico (Baja California Norte: Islas Las Encantadas: Isla El Muerto).


Crotalus oreganus

Northern Pacific Rattlesnake, Western Rattlesnake

Nördliche Pazifik-Klapperschlange

Nordvestlig Klapperslange

1840 Crotalus oreganus Holbrook
Crotalus confluentus oreganus Amaral 1929
Crotalus viridis oreganus Klauber 1936
1852 Crotalus lucifer Baird & Girard (Campbell & Lamar 2004)
Crotalus adamanteus lucifer Jan 1863
Caudisona lucifer Cope 1867
Crotalus confluentus lucifer Cope 1884
Crotalus oregonus lucifer Garman 1884
1868 Crotalus hallowelli Cooper in Cronise (Campbell & Lamar 2004)
1927 Crotalus oreganus niger Kallert [nomen nudum] (Campbell & Lamar 2004)
1930 Crotalus confluentus decolor Klauber (Campbell & Lamar 2004)
Crotalus viridis decolor Gloyd 1940

Remarks: Previously included abyssus, caliginis, cerberus, concolor, helleri, and lutosus. Regarded as a subspecies of viridis for more than half a century. Revalidated as a distinct species by Pook, Wüster & Thorpe (2000); Ashton & de Quieroz (2001); Douglas, Douglas, Schuett, Porras & Holycross (2002); and Campbell & Lamar (2004).
Distribution: Canada (British Columbia), USA (California, Idaho, Oregon, Washington).


Crotalus oreganus
© Rune Midtgaard

Crotalus ornatus

Northeastern Black-tailed Rattlesnake, Eastern Black-tailed Rattlesnake

Nordöstliche Schwarzschwanz-Klapperschlange

Nordøstlig Sorthalet Klapperslange

1854 Crotalus ornatus Hallowell

Remarks: Previously regarded as a synonym of molossus (e.g., Campbell & Lamar 2004). Revalidated as a separate species by Anderson & Greenbaum (2012).
Distribution: Mexico (Chihuahua, Coahuila, Nuevo Leon), USA (New Mexico, Texas).


Crotalus polisi

Isla Cabeza de Caballo Speckled Rattlesnake, Horsehead Island Speckled Rattlesnake

Isla-Cabeza-de-Caballo-Klapperschlange

Isla Cabeza de Caballo-klapperslange

2018 Crotalus polisi Meik, Schaack, Flores-Villela & Streicher

Distribution: Mexico (Baja California Norte: Isla Cabeza de Caballo).





Crotalus polystictus

Mexican Lance-headed Rattlesnake

Mexikanische Lanzenkopf-Klapperschlange

Lansehovedet Klapperslange

1859 Crotalus lugubris Jan [part] (Campbell & Lamar 2004)
1863 Crotalus lugubris var. multimaculata Jan [suppressed] (International Commission on Zoological Nomenclature 1955 (Opinion 366); Campbell & Lamar 2004)
1865 Caudisona polysticta Cope
Crotalus polystictus Cope 1875
1877 Crotalus Jimenezii Dugès (Campbell & Lamar 2004)
Crotalus triseriatus jimenezii Garman 1884

Distribution: Mexico (Aguascalientes, Distrito Federal, Guanajuato, Hidalgo, Jalisco, Mexico State, Michoacan, Morelos, Puebla, Queretaro, Veracruz, Zacatecas).


Crotalus polystictus
© Rune Midtgaard

Crotalus pricei

Twin-spotted Rattlesnake

Prices Klapperschlange

Dobbeltplettet Klapperslange

1895 Crotalus pricei Van Denburgh
Crotalus triseriatus pricei Klauber 1931
1940 Crotalus triseriatus miquihuanus Gloyd

Other common names:
miquihuanus: Eastern Twin-spotted Rattlesnake, Miquihuanan Rattlesnake
pricei: Western Twin-spotted Rattlesnake
Remarks: Reyes-Velasco, Grünwald, Jones, Price & Fisher (2012) provided the first vouchered record from San Luis Potosí, since Campbell & Lamar's (2004) inclusion of the state in the distribution was without references, and since no specimen from the state was found in collections (J. Reyes-Velasco, pers. comm., Oct. 9, 2012).
Distribution: Mexico (Aguascalientes, Chihuahua, Coahuila, Durango, Jalisco, Nayarit, Nuevo Leon, San Luis Potosi, Sonora, Tamaulipas, Zacatecas), USA (Arizona).


Crotalus pusillus

Tancitaran Dusky Rattlesnake, Southwestern Mexican Dusky Rattlesnake

Tancitaro-Klapperschlange

Sydvestmexicansk Mørk Klapperslange

1952 Crotalus pusillus Klauber

Remarks: Campbell & Lamar (1989) did not include the two Mexican states Mexico and Morelos in the distribution of the species, although McCranie (1976) listed both states.
Distribution: Mexico (Colima, Jalisco, Michoacan).


Crotalus pyrrhus

Southwestern Speckled Rattlesnake

Südwestliche Gefleckte Klapperschlange

Sydvestlig Spættet Klapperslange

1867 Caudisona pyrrha Cope "1866"
Crotalus pyrrhus Yarrow 1875
Crotalus confluentus pyrrhus Garman 1884
Crotalus mitchellii pyrrhus Stejneger 1895

Remarks: Previously regarded as a subspecies of mitchelli. Revalidated as a separate species by Meik, Streicher, Lawing, Flores-Villela & Fujita (2015).
Distribution: Mexico (Baja California Norte), USA (Arizona, California, Nevada, Utah).


Crotalus pyrrhus
© Rune Midtgaard

Crotalus ravus

Central Plateau Pygmy Rattlesnake, (Mexican Pygmy Rattlesnake)

Zentralmexikanische Zwergklapperschlange

Centralmexicansk Dværgklapperslange

1865 Crotalus ravus Cope
Caudisona rava Cope 1875
Crotalus miliarius var. ravus Garman 1884
Crotalophorus ravus Cope 1885
Sistrurus ravus Boulenger 1896
1978 Sistrurus ravus lutescens Harris & Simmons (Campbell & Armstrong 1979; Campbell & Lamar 2004)
1982 Sistrurus ravus sinaloensis Juliá-Zertuche [invalid name] (Campbell & Lamar 2004)

Other common names:
lutescens: Montane Pygmy Rattlesnake
ravus: Central Plateau Pygmy Rattlesnake, Mexican Massasauga
Remarks: Previously included brunneus and exiguus. Records from Guerrero and Oaxaca refer to exiguus and brunneus, respectively. Transferred back to the genus Crotalus by Murphy, Fu, Lathrop, Feltham & Kovac (2002), after having been considered a member of the genus Sistrurus for more than a century.
Distribution: Mexico (Distrito Federal, Hidalgo, Mexico State, Morelos, Puebla, Tlaxcala, Veracruz).


Crotalus ruber

Red Diamond Rattlesnake

Rote Diamantklapperschlange

Rød Diamantklapperslange, Rød Klapperslange

1884 Crotalus exsul Garman "1883" (International Commission on Zoological Nomenclature 2000: Opinion 1960; Campbell & Lamar 2004)
1892 Crotalus adamanteus ruber Cope
Crotalus ruber Van Denburgh 1896
Crotalus atrox ruber Stejneger 1895
Crotalus exsul ruber Kallert 1927
1920 Crotalus lucasensis Van Denburgh
Crotalus atrox lucasensis Schmidt 1922
Crotalus ruber lucasensis Klauber 1949
Crotalus exsul lucasensis Grismer, McGuire & Hollingsworth 1994
1922 Crotalus atrox elegans Schmidt (Campbell & Lamar 2004)
Crotalus ruber elegans Harris & Simmons 1978
1978 Crotalus ruber monserratensis Harris & Simmons (Campbell & Lamar 2004)

Other common names:
elegans: Angel de la Guarda Island Red Diamond Rattlesnake
exsul: Cedros Island Diamond Rattlesnake
lucasensis: San Lucan Red Diamond Rattlesnake
monserratensis: Monserrate Island Red Diamond Rattlesnake
ruber: Common Red Diamond Rattlesnake
Remarks: Previously included lorenzoensis. Although the name exsul has priority over ruber, the International Commission on Zoological Nomenclature has ruled that ruber should have precedence over exsul (International Commission on Zoological Nomenclature 2000: Opinion 1960).
Distribution: Mexico (Baja California Norte [incl. Isla Angel de la Guarda, Isla Cedros], Baja California Sur [incl. Isla San Jose, Isla San Marcos]), USA (California).


Crotalus ruber
© Rune Midtgaard

Crotalus scutulatus

Mojave Rattlesnake

Mojave-Klapperschlange

Mojave-klapperslange

1861 Caudisona scutulata Kennicott
Crotalus scutulatus Cope 1875
Crotalus adamanteus scutulatus Cope 1875
1895 Crotalus salvini Günther
Crotalus scutulatus salvini Gloyd 1940
1929 Crotalus confluentus kellyi Amaral (Campbell & Lamar 2004)

Other common names:
salvini: Huamantlan Rattlesnake, (Salvin's Rattlesnake)
scutulatus: Northern Mojave Rattlesnake, Mojave Green Rattlesnake
Distribution: Mexico (Aguascalientes, Chihuahua, Coahuila, Durango, Guanajuato, Hidalgo, Jalisco, Mexico State, Nuevo Leon, Puebla, Queretaro, San Luis Potosi, Sonora, Tamaulipas, Tlaxcala, Veracruz, Zacatecas), USA (Arizona, California, Nevada, New Mexico, Texas, Utah).


Crotalus scutulatus
© Rune Midtgaard

Crotalus simus

Central American Rattlesnake

Zentralamerikanische Klapperschlange

Centralamerikansk Klapperslange

1801 Crotalus simus Latreille in Sonnini & Latreille
1937 Crotalus terrificus copeanus Amaral [substitute name for Crotalus durissus Linnaeus 1758] (Campbell & Lamar 2004)
1978 Crotalus durissus neoleonensis Juliá-Zertuche & Treviño-Saldaña [nomen nudum] (Campbell & Lamar 2004)

Remarks: Previously included culminatus and tzabcan.
Distribution: Costa Rica, El Salvador, Guatemala, Honduras, Mexico (Chiapas), Nicaragua.


Crotalus stejnegeri

Northern Long-tailed Rattlesnake, Sinaloan Long-tailed Rattlesnake

Nördliche Langschwanz-Klapperschlange

Nordlig Langhalet Klapperslange

1919 Crotalus stejnegeri Dunn

Distribution: Mexico (Durango, Sinaloa).


Crotalus stephensi

Panamint Rattlesnake, Panamint Speckled Rattlesnake

Panamint-Klapperschlange

Panamint-klapperslange

1930 Crotalus confluentus stephensi Klauber
Crotalus mitchellii stephensi Klauber 1936
Crotalus stephensi Douglas, Douglas, Schuett, Porras & Thomason 2007

Distribution: USA (California, Nevada).


Crotalus tancitarensis

Tancitaro Rattlesnake

Tancitaro-Klapperschlange

Tancitaro-klapperslange

2004 Crotalus tancitarensis Alvarado-Díaz & Campbell

Distribution: Mexico (Michoacan).


Crotalus thalassoporus

Isla Piojo Speckled Rattlesnake, Louse Island Speckled Rattlesnake

Isla-Piojo-Klapperschlange

Isla Piojo-klapperslange

2018 Crotalus thalassoporus Meik, Schaack, Flores-Villela & Streicher

Distribution: Mexico (Baja California Norte: Isla Piojo).





Crotalus tigris

Tiger Rattlesnake

Tigerklapperschlange

Tiger-klapperslange

1859 Crotalus tigris Kennicott
Caudisona tigris Cope 1867

Distribution: Mexico (Sonora), USA (Arizona, New Mexico).


Crotalus tlaloci

Jaliscan Dusky Rattlesnake

Jalisco-Plateau-Klapperschlange

Mørk Jalisco-klapperslange

2014 Crotalus tlaloci Bryson, Linkem, Dorcas, Lathrop, Jones, Alvarado-Díaz, Grünwald & Murphy

Remarks: Previously regarded as a population of triseriatus (e.g., Campbell & Lamar 2004).
Distribution: Mexico (Guerrero, Mexico State, Michoacan, Morelos).


Crotalus tortugensis

Tortuga Island Diamondback Rattlesnake

Tortuga-Klapperschlange

Tortuga-diamantklapperslange

1921 Crotalus tortugensis Van Denburgh & Slevin
Crotalus atrox tortugensis Stejneger & Barbour 1933

Remarks: Regarded as a synonym of atrox by some authors (e.g., Castoe, Spencer & Parkinson 2007; Wilson & Johnson 2010; Wallach, Williams & Boundy 2014).
Distribution: Mexico (Baja California Sur: Isla Tortuga).


Crotalus totonacus

Totonacan Rattlesnake

Totonac-Klapperschlange

Totonac-klapperslange

1940 Crotalus totonacus Gloyd & Kauffeld
Crotalus durissus totonacus Smith & Taylor 1945
Crotalus basiliscus totonacus Taylor 1950
1978 Crotalus durissus neoleonensis Juliá-Zertuche & Treviño-Saldaña [nomen nudum] (Campbell & Lamar 2004)

Distribution: Mexico (Hidalgo, Nuevo Leon, Queretaro, San Luis Potosi, Tamaulipas, Veracruz).


Crotalus transversus

Cross-banded Mountain Rattlesnake

Quergebänderte Berg-Klapperschlange

Tværbåndet Klapperslange

1944 Crotalus transversus Taylor

Distribution: Mexico (Distrito Federal, Mexico State, Morelos).


Crotalus triseriatus

Mexican Dusky Rattlesnake

Mexikanische Plateau-Klapperschlange

Mexicansk Mørk Klapperslange

1830 Uropsophus triseriatus Wagler
Crotalus triseriatus Gray 1831
Caudisona triseriata Cope 1867
1859 Crotalus lugubris Jan [part] (Campbell & Lamar 2004)
Caudisona lugubris Cope 1860
1895 Crotalus pallidus Günther (Campbell & Lamar 2004)
1940 Crotalus triseriatus anahuacus Gloyd (part) (Campbell & Lamar 2004)

Other common names:
anahuacus: Montane Dusky Rattlesnake
quadrangularis: Hidalgan Dusky Rattlesnake
triseriatus: Central Plateau Dusky Rattlesnake
Remarks: Previously included aquilus, armstrongi and the populations now known as campbelli and tlaloci (Bryson, Linkem, Dorcas, Lathrop, Jones, Alvarado-Díaz, Grünwald & Murphy 2014).
Distribution: Mexico (Distrito Federal, Hidalgo, Mexico State, Michoacan, Morelos, Puebla, Queretaro, Tlaxcala, Veracruz).


Crotalus tzabcan

Yucatan Rattlesnake, Yucatan Neotropical Rattlesnake

Yucatan-Klapperschlange

Yucatan-klapperslange

1952 Crotalus durissus tzabcan Klauber
Crotalus simus tzabcan Campbell & Lamar 2004
Crotalus tzabcan Wüster, Ferguson, Quijada-Mascareñas, Pook, Graca-Salomão & Thorpe 2005

Distribution: Belize, Guatemala, Mexico (Campeche, Quintana Roo, Tabasco, Yucatan).


Crotalus unicolor

Aruba Rattlesnake, Aruba Dwarf Rattlesnake, Aruba Cascabel

Aruba-Klapperschlange

Aruba-klapperslange

1887 Crotalus horridus var. unicolor Van Lidth de Jeude
Crotalus unicolor Klauber 1936
Crotalus durissus unicolor Brongersma 1940

Remarks: Regarded by some authors as a subspecies of durissus (e.g., Campbell & Lamar 2004; Wallach, Williams & Boundy 2014; David, Dobiey & Vogel 2018), but treated as a valid species here, following Buurt (2005). Reports from Nicaragua (e.g., Golay & al. 1993) must be in error.
Distribution: Aruba.


Crotalus unicolor
© Rune Midtgaard

Crotalus vegrandis

Uracoan Rattlesnake

Uracoan-Klapperschlange

Venezuelansk Klapperslange

1941 Crotalus vegrandis Klauber
Crotalus durissus vegrandis Klauber 1956

Remarks: Regarded by some authors as a subspecies of durissus (e.g., Campbell & Lamar 2004; David, Dobiey & Vogel 2018), but treated as a valid species here, following Rivas, Molina, Ugueto, Barros, Barrio-Amorós & Kok (2012). Not listed for Venezuela by Mumaw, González & Fernández (2015), who presumably considered the taxon a synonym of durissus.
Distribution: Venezuela.


Crotalus vegrandis
© Rune Midtgaard

Crotalus viridis

Prairie Rattlesnake

Prärie-Klapperschlange, (Westliche Klapperschlange)

Prærieklapperslange

1818 Crotalinus viridis Rafinesque
Crotalurus viridis Rafinesque 1820
1823 Crotalus confluentus Say in James (Campbell & Lamar 2004)
Caudisona confluenta Cope 1867
1852 Crotalus Lecontei Hallowell (Campbell & Lamar 2004)
Caudisona confluenta lecontei Cope 1867
Crotalus confluentus lecontei Cope 1892
1883 Crotalus confluentus var. pulverulentus Cope (Campbell & Lamar 2004)
1935 Crotalus confluentus nuntius Klauber
Crotalus viridis nuntius Klauber 1936

Other common names:
nuntius: Hopi Rattlesnake
viridis: Prairie Rattlesnake
Remarks: Previously included abyssus, caliginis, cerberus, concolor, helleri, lutosus, and oreganus.
Distribution: Canada (Alberta, Saskatchewan), Mexico (Chihuahua, Coahuila, Sonora), USA (Arizona, California, Colorado, Idaho, Iowa, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wyoming).


Crotalus viridis
© Rune Midtgaard

Crotalus willardi

Ridge-nosed Rattlesnake

Kantenkopf-Klapperschlange

Spidssnudet Klapperslange

1905 Crotalus willardi Meek
1949 Crotalus willardi meridionalis Klauber
1949 Crotalus willardi silus Klauber
1962 Crotalus willardi amabilis Anderson
1974 Crotalus willardi obscurus Harris

Other common names:
amabilis: Del Nido Ridge-nosed Rattlesnake
meridionalis: Southern Ridge-nosed Rattlesnake
obscurus: Animas Ridge-nosed Rattlesnake, New Mexico Ridge-nosed Rattlesnake
silus: Chihuahua Ridge-nosed Rattlesnake
willardi: Arizona Ridge-nosed Rattlesnake
Distribution: Mexico (Chihuahua, Durango, Nayarit, Sonora, Zacatecas), USA (Arizona, New Mexico).


Crotalus willardi
© Rune Midtgaard