Sonoran Desert Sidewinder

Crotalus cerastes cercobombus

''Crotalus cerastes cercobombus'' is a venomous pitviper subspecies found in an area that covers much of the eastern part of the Sonoran Desert in the southwestern United States and northwestern Mexico. The subspecific epithet means ''buzzertail.''
Sonoran Desert Sidewinder on a warm road at night  Animal,Crotalus cerastes cercobombus,Geotagged,Summer

Appearance

This form has the following distinguishing characteristics: the proximal rattle-matrix lobe is black in adult specimens, the ventral scales number 132-144/138-148 in males/females, the subcaudals number 18-24/14-19 in males/females, and there are usually less than 21 rows of midbody dorsal scales.

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Taxonomy
KingdomAnimalia
DivisionChordata
ClassReptilia
OrderSquamata
FamilyViperidae
GenusCrotalus
SpeciesC. cerastes