Massasauga
The massasauga (Sistrurus catenatus) is a rattlesnake species found in southern Ontario, northern Mexico, and parts of the United States. Three subspecies are currently recognized including the nominate subspecies described here. As with all rattlesnakes, it is a pit viper (and as with all pit vipers, it is venomous).
Description
The adults are not large, ranging from 60 to 75 cm (24 to 30 in) in length. The color pattern consists of a grey or tan ground color with a row of large rounded brown/black blotches or spots down the center of the back and three smaller rows of alternating spots down each side. Solid black melanistic examples are also known, as well as cases where the back blotches join with those on the sides. Young massasauga are well-patterned but paler than the adults. It has heat-sensing pits on each side of its smallish head, the scales are keeled and the anal scale is single.
Common names
Massasauga, massasauga rattlesnake, massasauga rattler (Ontario), black massasauga, black rattler, black snapper, gray rattlesnake (Iowa), little grey rattlesnake (Canada), muck rattler, prairie rattlesnake, spotted rattler, swamp rattler, víbora de cascabel (Mexico), dwarf prairie rattlesnake, eastern massasauga great adder, ground rattlesnake, Kirtland's rattlesnake, little black rattlesnake, Michigan point rattler (Michigan), prairie massasauga, rattlesnake, small prairie rattlesnake, snapper, swamp massasauga, swamp rattlesnake, and triple-spotted rattlesnake.