Specific Snakes

The main families, and what sets each apart.

Snake families differ in fang arrangement, venom chemistry and hunting method. Those differences matter medically as well as biologically — antivenoms are family and often species specific.

Vipers (Viperidae)

Long hinged fangs that fold back when the mouth closes, allowing greater length than the head would otherwise permit. Venom is typically haemotoxic, damaging tissue and blood. Includes rattlesnakes, copperheads, cottonmouths and the true vipers and adders. Pit vipers add infrared-sensing pits between eye and nostril.

Elapids (Elapidae)

Short fixed fangs at the front of the mouth. Venom is usually neurotoxic, acting on the nervous system. Cobras, mambas, kraits, coral snakes and all sea snakes. Several cobras can spray venom defensively toward the eyes.

Colubrids (Colubridae)

The largest family, well over half of all snakes, and most are harmless to people. Includes rat snakes, king snakes, garter snakes and grass snakes. A few rear-fanged members such as the boomslang are genuinely dangerous, so 'colubrid' is not a synonym for safe.

Constrictors

Pythons and boas kill by constriction rather than venom. Each exhalation lets the coils tighten, and death results from circulatory arrest rather than suffocation as long assumed. Pythons lay eggs; boas give birth to live young — a reliable way to tell the two groups apart.