Crotalus vegrandis, or the Uracoan Rattlesnake, is a venomous pit viper that is endemic to Venezuela.
Klauber (1997) gives two maximum lengths: 636 mm for the largest measured specimen, and 684 mm as the greatest value from a report believed to be reliable.
The species only occurs in its type locality of the MaturÃÂn Savannah, near the Uracoa Municipality, within the state of Monagas.