What is the most poisonous snake in the Mojave Desert?

Crotalus scutulatus (common names: Mohave rattlesnake, is probably the most venomous snake in the Mojave Desert. Its venom contains a neurotoxic component that is capable of killing a human being in just a few hours.

Just as a point of clarification, a poison is a substance that one must eat to be affected. A venom, such as that of a snake, must be injected. Therefore, a snake is venomous, not poisonous. Most snake venoms can be safely consumed with no problems (as long as you do not have an open sore in your mouth or stomach or digestive tract. The venom must get into the blood stream to kill.