Crotalus molossus nigrescens
GLOYD 1936
Sonora, Mexico. August 22, 2011
Road cruising a mountain road one rainy night, just a few miles from the border with Chihuahua, this rattlesnake appeared in the headlights. It was the first of of several Blacktails I saw on my first trip to Mexico. One of the things I like about molossus is that each dorsal scale is of a single color, making for distinct and beautiful patterns.
My Flickr album for this species is here.