Western Diamondback Rattlesnake

                                    

                                          

The western diamondback rattlesnake or Texas diamond-back (Crotalus atrox) is a   and member of the viper family, found in the  and . Like all other rattlesnakes and all other vipers, it is . It is likely responsible for the majority of snakebite fatalities in northern Mexico and the greatest number of snakebites in the U.S. No subspecies are currently recognized.
Other common names for this species include western diamond-backed rattlesnake, adobe snake, Arizona diamond rattlesnake, coon tail, desert diamond-back, desert diamond rattlesnake, fierce rattlesnake, spitting rattlesnake, buzz tail, Texan rattlesnake, Texas diamond-back, and Texas rattler.

Its habitats range from flat coastal plains to steep rocky canyons and hillsides; it is associated with many different vegetation types, including , sandy  areas,  grassland, , and pine-oak forests. Frequently roaming during the day, it is common to see the western diamondback when ambient temperatures drop because of the heat retention of blacktop roads.
C. atrox is  except during the mating season, when males of the species are single-minded and aggressive in pursuing females. Usually inactive between late October and early March, these  occasionally may be seen basking in the sun on warm winter days. In the winter, they  or  in caves or burrows, sometimes with many other species of snakes. Active, alert, and large (most adults are between four and a half and five feet long), the western diamondback can administer a large amount of venom in its bite; it is not inclined to give ground when confronted. 
They are poor climbers. Natural predators include  such as hawks and eagles, , wild hogs, and other snakes. When threatened, they usually coil and rattle to warn aggressors. They are one of the more defensive rattlesnake species in the US in the way that they stand their ground when confronted by a foe. If rattling does not work, then the snake will strike in defense.