Eastern Hognose Snake, Puff Adder, Hissing Adder, Spreading Adder, Blow Viper, Hissing Sand Snake
Scientific name: Heterodon platirhinos (LATREILLE 1801)
* Currently accepted name
* scientific names used through time
- Heterodon platirhinos – LATREILLE 1801
- Heterodon platyrhinos – BAIRD & GIRARD 1853
- Heterodon platyrhinus [sic] – DUMÉRIL, BIBRON & DUMÉRIL 1854
- Heterodon niger – DUMÉRIL & BIBRON 1854 (fide WALLACH)
- Coluber heterodon – DAUDIN 1803
- Heterodon browni – STEJNEGER 1903
- Heterodon contortrix – ALLEN 1932
Description: Average adult size is 20-33 inches (51-84 cm), record is 45.5 inches (115.5 cm). It has a thick body and slightly upturned, pointed snout. Adult coloration is extremely variable and may be mostly yellow, tan, olive, brown, gray, orange, or reddish-brown with dark brown or black large, irregular shaped blotches on the back and smaller blotches on the sides. Some individuals may be entirely black or dark gray without any pattern. The belly may be yellow, light gray, or pinkish and may or may not be mottled gray or greenish. The underside of the tail is lighter than the rest of the belly. There is a dark line extending from the upper jaw through the eye. The scales are keeled, and there are 23-25 dorsal scale rows at midbody. The pupil is round.
A. Side of the head
B. Top of the head
C. Front (face view) of the head
D. Keeled scales
E. Elongated scales below the tail (subcaudal scales) are typically divided
Range: It is found throughout Florida, excluding the Keys. Outside of Florida, it is found throughout the eastern US from Florida and Texas north to Minnesota, east to southern Ontario and Quebec and southern New Hampshire.
Habitat: It locally abundant in certain habitats including sandhills, scrub, high pine and turkey oak woodlands, hardwood hammocks, meadows, and cultivated fields.
Comments: HARMLESS (Non-Venemous).
Heterodon means "different tooth," which refers to the enlarged teeth on the rear of the upper jaw. These teeth inject a mild venom into its prey, and also serve to pop inflated toads like a balloon to enable swallowing. They use their blunt nose to search through leaf litter and soil for prey.
Adults mainly eat toads, but will sometimes eat other frogs, insects, and invertebrates. Juveniles eat small frogs and toads, insects, lizards, and small snakes.
It lays eggs. Breeding takes place in both the spring and fall. Males often follow the female around for several days prior to courtship and copulation. They lay between 4-61 whitish, thin shelled, leathery eggs 1.25 inches (3.2 cm) long. Eggs are deposited in a moist sandy, shallow hole, or under debris, and hatch in 39-65 days. Hatchlings are 6.5-9.5 inches (16-24 cm).
The Hognose Snake is renowned for its "death feigning" behavior. When threatened, it flattens its head and neck and hisses loudly. It may strike, but only with its mouth closed. If it is further harassed, it will flip on its back and convulse for a short period and may defecate and regurgitate its food. It will then remain motionless with its belly up, mouth open, and tongue hanging out. It may play dead for several minutes before cautiously turning over, looking around to see if it is safe before crawling away.
Flattening its head and hissing when it is frightened gave rise to two of the local names used for this snake. The banded form of the Hognose Snake is often called a "Puff Adder" and is correctly believed to be harmless. However, the black form of the Hognose Snake is called a "Spreading Adder" and is wrongly believed to be deadly. Both color forms of the Eastern Hognose Snake are harmless to humans. However, humans that are allergic to its small amount of venom have been known to produce local swelling, but no human death has ever occurred.
Another old myth says that the Hognose Snake can mix venom with its breath and is thus able to kill a person from a distance of twenty-five feet. In truth, its breath is harmless.
Comparison with other species: The Southern Hognose Snake (Heterodon simus) has a light-colored belly and underside of the tail, and a more upturned snout. Hognose Snakes are often confused with the Pigmy Rattlesnake (Sistrurus miliarius), which has a blunt nose — it is easy to distinguish between the harmless Hognose Snakes and the Pigmy Rattlesnake.