The western pygmy rattlesnake is Missouri’s smallest venomous snake (usually less than two feet in length). As is the case with any venomous snake, this creature has few friends among humans. However, it should be noted that pygmy rattlesnakes benefit us by consuming mice and other small rodents that can be pests to humans.
Species: Western pygmy rattlesnake
Scientific name: Sistrurus miliarius streckeri
Nicknames: ground rattler
Claim to fame: The western pygmy rattlesnake is Missouri’s smallest venomous snake (usually less than two feet in length). As is the case with any venomous snake, this creature has few friends among humans. However, it should be noted that pygmy rattlesnakes benefit us by consuming mice and other small rodents that can be pests to humans.
Species status: Because of their primarily nocturnal behavior in summer and also because of their skittish nature, pygmy rattlesnakes aren’t frequently seen. However, they can be found in this area and throughout much of southern Missouri.
First discovered: The first scientific description of the pygmy rattlesnake was written by the famed naturalist Carl Linnaeus in 1766. The first description of the western pygmy was written by Kansas herpetologist Howard K. Gloyd in 1935.
Family matters: The western pygmy rattlesnake belongs to the family Viperidae, a group commonly referred to as the venomous snakes. There are three subspecies of pygmy rattlesnakes in North America. Besides the western, there’s the Carolina pygmy (Sistrurus miliarius miliarius) and the dusky pygmy (Sistrurus miliarius barbouri).
Length: 15 to 20 inches
Diet: lizards, small snakes, mice and occasionally insects and small frogs
Weight: Adults can weigh between one and six ounces.
Distinguishing characteristics: The general color of the western pygmy is brownish gray with dark brown or black blotches. The head has a distinct black stripe that angles from the eye to the corner of the mouth. A narrow orange-brown dorsal stripe is usually present. The sound made by the rattle is a faint buzz reminiscent of the sound of an insect. It can be heard only slightly over a meter away.
Life span: Pygmy rattlesnakes have been known to live up to 15 years.
Habitat: During late spring and early summer, pygmy rattlesnakes will bask in rocky open areas, near brushpiles, or along the sides of roads near forests and glades. During July and August, this species tends to be nocturnal and can be observed crossing roads and highways at night. This species takes shelter under rocks during spring, early summer and autumn. Other retreats include abandoned mammal burrows, logs and brushpiles.
Life cycle: Courtship and mating are presumed to take place in the spring. The young are born from August through September. Pygmy rattlesnakes give birth to live young (they’re ovoviviparous) as opposed to laying eggs. Three to seven young are produced per litter. As is the case with most species of snakes, pygmy rattlesnakes provide no parental care to their offispring. The young are on their own at birth.