The Crotalinae, commonly known as pit vipers, or pit adders, are a subfamily of vipers found in Eurasia and the Americas. Like all other vipers, they are venomous. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on both sides of the head. Currently, 23 genera and 155 species are recognized: These are also the only viperids found in the Americas. The groups of snakes represented here include rattlesnakes, lanceheads, and Asian pit vipers. The type genus for this subfamily is Crotalus, of which the type species is the timber rattlesnake, C. horridus.
Agkistrodon is a genus of venomous pit vipers commonly known as American moccasins. The genus is endemic to North America, ranging from the Southern United States to northern Costa Rica. Eight species are currently recognized, all of them monotypic and closely related. Common names include: cottonmouths, copperheads, and cantils.
The Viperidae (vipers) are a family of snakes found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, New Zealand, and various other isolated islands. They are venomous and have long, hinged fangs that permit deep penetration and injection of their venom. Three subfamilies are currently recognized. They are also known as viperids. The name "viper" is derived from the Latin word vipera, -ae, also meaning viper, possibly from vivus ("living") and parere, referring to the trait viviparity common in vipers like most of the species of Boidae.
Sistrurus is a genus of venomous pit vipers in the subfamily Crotalinae of the family Viperidae. The genus is endemic to Canada, the United States, and Mexico. Its generic name is a Latinized form of the Greek word for "tail rattler" and shares its root with the ancient Egyptian musical instrument, the sistrum, a type of rattle. Three species are currently recognized.
Cerastes cerastes, commonly known as the Saharan horned viper or the desert horned viper, is a venomous species of viper native to the deserts of Northern Africa and parts of the Arabian Peninsula and Levant. It is often easily recognized by the presence of a pair of supraocular "horns", although hornless individuals do occur. Three subspecies have been described.
Snake venom is a highly toxic saliva containing zootoxins that facilitates in the immobilization and digestion of prey. This also provides defense against threats. Snake venom is injected by unique fangs during a bite, whereas some species are also able to spit venom.
Lachesis muta, also known as the Southern American bushmaster or Atlantic bushmaster, is a venomous pit viper species found in South America, as well as the island of Trinidad in the Caribbean. Two subspecies are currently recognized, including the nominate subspecies described here.
Bothrops leucurus, commonly known as the whitetail lancehead or the Bahia lancehead, is a species of venomous snake, a pit viper in the family Viperidae. The species is endemic to Brazil. There are no subspecies which are recognized as being valid. A female owned by youtuber Venom Central is over six feet long.
Echis is a genus of vipers found in the dry regions of Africa, the Middle East, India, Sri Lanka and Pakistan. They have a characteristic threat display, rubbing sections of their body together to produce a "sizzling" warning sound. The name Echis is the Latin transliteration of the Greek word for "viper" (ἔχις). Like all vipers, they are venomous. Their common name is "saw-scaled vipers" and they include some of the species responsible for causing the most snakebite cases and deaths in the world. Twelve species are currently recognized.
The western diamondback rattlesnake or Texas diamond-back is a rattlesnake species and member of the viper family, found in the southwestern United States and Mexico. Like all other rattlesnakes and all other vipers, it is venomous. It is likely responsible for the majority of snakebite fatalities in northern Mexico and the greatest number of snakebites in the U.S. No subspecies are currently recognized.
Calloselasma is a monotypic genus created for a venomous pit viper species, Calloselasma rhodostoma, which is endemic to Southeast Asia from Thailand to northern Malaysia and on the island of Java. No subspecies are currently recognized.
Vipera aspis is a viper species found in southwestern Europe. Its common names include asp, asp viper, European asp, and aspic viper, among others. Like all other vipers, it is venomous. Bites from this species can be more severe than from the European adder, V. berus; not only can they be very painful, but approximately 4% of all untreated bites are fatal. The specific epithet, aspis, is a Greek word that means "viper." Five subspecies are currently recognized, including the nominate subspecies described here.
Lachesis stenophrys, commonly called the Central American bushmaster, is a species of venomous pit viper in the family Viperidae. The species is native to Central America.
Lachesis acrochorda, also known commonly as the Chocoan bushmaster, is a species of venomous pit viper in the family Viperidae. The species is native to Central America and South America.
Lachesis melanocephala is a species of venomous pit viper in the family Viperidae. The species is native to Costa Rica and Panama. There are no subspecies that are recognized as being valid.
Bothrops moojeni, commonly known in English as the Brazilian lancehead, is a species of venomous snake in the family Viperidae. It is a pit viper endemic to South America.
Snakebite envenomation is considered a public health problem in Latin America, with an estimated 70,000 cases annually, but due to underreporting, these numbers may be even higher.
