A subfamily of snakes commonly known as true vipers or crotaline snakes in the family VIPERIDAE. They are distinguished from sister subfamily CROTALINAE or pit vipers by their lack the heat-sensing pit organs.
A subfamily of snakes commonly known as true vipers or crotaline snakes in the family VIPERIDAE. They are distinguished from sister subfamily CROTALINAE or pit vipers by their lack the heat-sensing pit organs.