viperid

Viperid refers to a member of the snake family Viperidae, a group of venomous snakes found worldwide. The family is divided into two subfamilies: Viperinae (true or old world vipers) and Crotalinae (pit vipers). Members share a stout body and a generally triangular head, and most have long hinged fangs (solenoglyphous) that fold back when not in use. In pit vipers (Crotalinae) a pair of heat-sensing pits between the eyes and nostrils helps detect warm-blooded prey.

Venom is primarily proteinaceous and can be cytotoxic, causing tissue damage, swelling, pain, and sometimes coagulopathy or systemic effects. Potency and venom composition vary among species. Envenomation can be life-threatening and typically requires prompt medical care and antivenom where available.

Distribution is global in warm and temperate regions, including Africa, Asia, Europe, the Americas, and parts of Oceania. Habitats range from deserts and grasslands to forests and mountains. Viperids are usually ambush predators, feeding on small vertebrates such as rodents, birds, and amphibians. Reproduction is diverse: many species are ovoviviparous, giving birth to live young, while others lay eggs.

Notable genera commonly cited among viperids include Vipera (European vipers), Bothrops (Americas), Crotalus and Sistrurus (rattlesnakes), Lachesis (bushmasters), and Echis (saw-scaled vipers). Taxonomy is complex and subject to revision as new data emerge.

Conservation status varies by species; threats include habitat loss, persecution, and collection for venom or the pet trade. Viperids are studied for their venoms, which contain components of medical and research interest.