This is a light color phase, Santa Catalina Rattlesnake (Crotalus catalinensis). It is a medium size rattlesnake, and its main identifying characteristic, is that it "has no rattle.” The snake’s tail only produces buttons that fall off every time it sheds its skin. As the name implies, this rattlesnake is only found on the Island of Santa Catalina in the Gulf of California, Mexico.
This is a Mexican Lance-headed Rattlesnake (Crotalus polystictus). They are a small rattlesnake, that is native to central Mexico. They are also called; Mexican lanceheaded rattlesnake, Lance-headed Rattlesnake, or Víbora-cascabel Ocelada (Spanish).