Crotalus willardi silus

Crotalus willardi silus is recognisable as it has less conspicuous markings than its sister subspecies. Its head is brown with irregular dark spots, it has a dark ocular band starting dark brown at the corner of the eyes and fades to grey as it reaches the end of the supralabials and the front of the head is usually grey. It lacks the facial markings seen in other subspecies of C. willardi.

Dorsally, the snake is brown or red with blotched and dotted with brown markings.{{Cite journal |last=Van Devender |first=Thomas R. |last2=Lowe |first2=Charles H. |date=1977 |title=Amphibians and Reptiles of Yepómera, Chihuahua, Mexico |url=https://www.jstor.org/stable/1563290?seq=8 |journal=Journal of Herpetology |volume=11 |issue=1 |pages=41–50 |doi=10.2307/1563290 |issn=0022-1511|url-access=subscription }} Its rattle is dark brown and rounded, with sharp scales as a sheath for it, as is characteristic of the species.{{Cite book |last=San Diego Society of Natural History. |url=https://www.biodiversitylibrary.org/item/28518#page/141/mode/1up |title=Transactions of the San Diego Society of Natural History |last2=History |first2=San Diego Society of Natural |date=1946 |publisher=The Society |volume=v.11 (1946-1953) |location=[San Diego]}}

It is also a smaller snake, measuring up to 63.6 cm (25 in).

Crotalus willardi silus has been recorded to eat rodents.{{Cite book |last=Brigham Young University. |url=https://www.biodiversitylibrary.org/page/8885537#page/696/mode/1up |title=The Great Basin naturalist |last2=University |first2=Brigham Young |last3=University |first3=Brigham Young |last4=Museum |first4=M. L. Bean |date=1985 |publisher=M.L. Bean Life Science Museum, Brigham Young University |volume=v.45 (1985) |location=Provo, Utah}}

Crotalus willardi silus is known to be ovoviviparous.

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willardi silus

Category:Reptiles described in 1949

Category:Reptiles of the Americas

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