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Crotalus willardi MEEK, 1905

IUCN Red List - Crotalus willardi - Least Concern, LC

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Higher TaxaViperidae, Crotalinae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)
SubspeciesCrotalus willardi amabilis ANDERSON 1962
Crotalus willardi meridionalis KLAUBER 1949
Crotalus willardi obscurus HARRIS 1974
Crotalus willardi silus KLAUBER 1949
Crotalus willardi willardi MEEK 1905 
Common NamesE: willardi: Arizona Ridgenose Rattlesnake; obscurus: New Mexico Ridgenose Rattlesnake; amabilis: Del Nido Ridge-nosed Rattlesnake; meridionalis: Southern Ridge-nosed Rattlesnake; silus: Western Chihuahuan Ridge-nosed Rattlesnake)
G: Willards Klapperschlange, Kantenkopf-Klapperschlange
S: Cascabel de Nariz-afilada 
SynonymCrotalus willardi willardi MEEK 1905
Crotalus willardi MEEK 1905
Crotalus willardi willardi — KLAUBER 1949
Crotalus willardi willardi — STEBBINS 1985: 234
Crotalus willardi willardi — LINER 1994
Crotalus willardi — MCDIARMID, CAMPBELL & TOURÉ 1999: 300
Crotalus willardi — ERNST & ERNST 2003: 548
Aechmophrys (Cottonus) willardi — HOSER 2009
Crotalus willardi — CROTHER et al. 2012
Crotalus willardi — WALLACH et al. 2014: 196

Crotalus willardi amabilis ANDERSON 1962
Crotalus willardi amabilis ANDERSON 1962
Crotalus willardi amabilis — TANNER 1985: 665
Crotalus willardi amabilis — LINER 1994
Crotalus willardi amabilis — BRYSON 2007

Crotalus willardi meridionalis KLAUBER 1949
Crotalus willardi meridionalis KLAUBER 1949
Crotalus willardi meridionalis — KLAUBER 1952: 109
Crotalus willardi meridionalis — LINER 1994
Crotalus willardi meridionalis — BEAMAN & HAYES 2008

Crotalus willardi obscurus HARRIS & SIMMONS 1974
Crotalus willardi obscurus HARRIS & SIMMONS 1974: 23
Crotalus willardi obscurus — STEBBINS 1985: 234
Crotalus willardi obscurus — LINER 1994
Crotalus willardi obscurus — BRYSON 2007
Crotalus obscurus — HERRMANN 2016

Crotalus willardi silus KLAUBER 1949
Crotalus willardi silus KLAUBER 1949
Crotalus willardi silus — KLAUBER 1952: 110
Crotalus willardi silus — VAN DEVENDER & LOWE 1977
Crotalus willardi silus — TANNER 1985: 666
Crotalus willardi silus — LINER 1994
Crotalus willardi silus — BRYSON 2007 
DistributionUSA (SE Arizona: Santa Rita Mountains, Patagonia Mountains, Canelo Hills-Huachuca Mountains, Whetstone Mountains; SW New Mexico),
Mexico (Sonora, Chihuahua, Nayarit, Durango: Sierra Madre Occidental and associated highlands)

willardi: USA (S Arizona), Mexico (N Sonora); Type locality: Tombstone, Arizona; emended to "the Huachucas [Mountains], ... a short distance above Hamburg in the middle branch of Ramsey Canyon, ... at about 7000 feet" elevation by SWARTH 1921.

amabilis: Mexico (Sierra del Nido, Chihuahua); Type locality: "Arroyo Mestefio, 8,500 feet, Sierra del Nido, Chihuahua, Mexico."

meridionalis: Mexico (S Durango, NW Zacatecas); Type locality: "Coyotes, Durango, Mexico, at elevation 8000 ft." (on the railroad to EI Salto, according to Klauber 1949: 131).

obscurus: Mexico (NE Sonora, NW Chihuahua), USA (S Arizona: Peloncillo Mountains; Bryan Starrett, pers. comm.). Type locality: "one canyon in the Animas Mountains," [New Mexico, USA] in original description; subsequently given as "upper end Indian Creek Canyon, Animas Mountains, Hidalgo County, New Mexico" by Harris and Simmons (1976:5).

silus: Mexico (NE Sonora, W Chihuahua), USA (SW New Mexico); Type locality: "on the Rio Gavilan, 7 miles southwest of Pacheco Chihuahua, Mexico, elevation 6200 ft."  
TypesHolotype: FMNH 902
Holotype: USNM 195546, designated by Harris and Simmons, 1976 [obscurus]
Holotype: MVZ 68896 [amabilis]
Holotype: SDNHM = SDSNH 6569 [meridionalis]
Holotype: MVZ 46694 [silus] 

Nomenclature: Hoser’s 2009 classification and nomenclature has been rejected as unnecessary and unavailable by WÜSTER & BERNILS 2011. 
Etymologynamed for Professor F. C. Willard, of Tombstone, Arizona, its discoverer. 
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