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Mexican Black-tailed Rattlesnake

Crotalus molossus nigrescens


About 90cm long. Brown colouration which becomes lighter on the flanks; pale yellow cross bands run from the head to the beginning of the tail; the tail is completely black, which gives the species its common name. This species is considered one of the more docile rattlers and bites are rare. It is venomous, though, but the toxicity is somewhat lower than other rattlers. This particular specimen rattled strongly and proceeded to, rather slowly, move toward a tree and assume its defensive S-shaped position against the tree trunk (picture #3).


Semi-arid region in central Mexico during rainy season.

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Felix Fleck
Felix Fleck a year ago

Yeah! My first sighting of a rattler, and I get such an impressive one!

LaurenZarate a year ago

Wow. Impressive rattler! Must be an old guy.

Felix Fleck
Spotted by
Felix Fleck

Querétaro, Mexico

Spotted on Sep 20, 2018
Submitted on Sep 21, 2018

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