(1) Colubridae
Colubridae
The Colubridae is the largest family of reptiles with up to 300 genera and 1600-1800 species, including 2/3 of the existing snakes, and it is found in every continent of the world and is the main snake species in all places except Australia. The members of the family Viperidae are very complex, equivalent to a shelter for progressive snakes, with many subfamilies and confusing divisions, and sometimes some members are listed as independent families, the most controversial of which is the cave viper distributed in Africa and the Middle East, which has some similarities with members of the families of the suborder Neosnake, but is not closely related, and is sometimes listed as a single family, the cave viper family, the Atractaspididae (right photo). The majority of Atractaspididae are non-venomous snakes, and some are posteriorly fanged vipers, most of which are not very venomous, but there are a few highly venomous species and a few frontal fang species. Members of the family Swimming Snakes are morphologically diverse, with some species having several different patterns in a single species, most notably the American kingsnake Lampropeltis getula and the milksnake Lampropeltis triagulum (below left). There are more than 10 subspecies of kingsnakes, which are so different from each other that they are often mistaken for different species from the outside. There are as many as 25 subspecies of milk snakes, which are non-venomous but so similar in appearance to the highly venomous coral snakes that the different subspecies of milk snakes look very much like different species of coral snakes. The most exotic members of the Swimming Snake family are the Chrysopelea (below right), several members of the genus Chrysopelea found in tropical Asia, which can glide some distance in the air and are known as flying snakes. The highly venomous members of the Swimming Snake family are found mainly in Africa, such as the African Tree Snake, Dispholidus (bottom center), and the African Vine Snake, Thelotornis, both of which can be fatally poisonous and whose venom has no antitoxin yet.
(2) Cobra family Elapidae
There are more than 310 species in over 70 genera in the cobra family, which are venomous snakes with anterior sulcus teeth. The cobra family is widely distributed in all warm regions of the world, both on land and in the sea, with Australia being the dominant snake. Cobra family is often divided into terrestrial cobras Elapidae and marine sea snakes Hydrophiidae 2 families, and sea snakes are often divided into flat-tailed snakes Laticaudidae still have to rely on land to reproduce and highly adapted to the sea life of sea snakes Hydrophiidae 2 families. Most members of the family Cobra are morphologically similar to the family Viperidae, but a few species, such as the Oceanic spiny snake Acanthophis, are very similar in size to members of the family Viperidae, which may be related to the absence of true members of the family Viperidae in Oceania. The fangs of members of the cobra family cannot be folded and retracted, so the fangs cannot be too large and are much smaller than those of members of the viper family, with the largest cobras having fangs no larger than those of the smallest vipers, but members of the cobra family tend to be much more venomous, with the most venomous snake on land being Australia's inland tephritid snake (the fine-scaled tephritid snake), Oxyuranus microlepidotus (above left), whose A single discharge of venom can kill up to 250,000 rats! And some species of sea snakes can be even more venomous! There are 45 genera and 250 species of terrestrial cobras, with some notable species in Oceania, Asia, Africa and the Americas. Cobras are dominant in Oceania, where they occupy a relatively diverse ecological niche due to the lack of other snakes. Well-known species include the tiger snake Notechis, the Iowan snake Pseudechis, and others, in addition to the aforementioned Tephritids and Echinodermata, with the genus Iowan comprising Australia's most common and widely distributed venomous snakes. The most famous Asian cobra is the king cobra Ophiophagus hannah (above right), which is the largest venomous snake in the world, with a body length of more than 5 meters. African cobras are best known for the mamba snake Dendroaspis (bottom right), which is mainly arboreal, but the black mamba snake Dendroaspis polylepis is often found on the ground, and is the largest cobra in Africa, with a body length of up to 4 meters. The black mamba snake is also the most venomous snake in Africa and is very dangerous because of its agility and fast attack speed. There are also several species of venom-spewing cobras in Asia and Africa that primarily attack the eyes of their opponents. Cobras in the Americas are represented by the coral snakes Micrurus and the anthropomorphic coral snakes Micruroides, which are among the most colorful snakes and one of the most venomous in the Americas, and some non-venomous snakes in the Americas, such as the Milk Snake, anthropomorphize into coral snakes to protect themselves. There are one genus and six species of flat-tailed snakes, most of which are found offshore in the tropics of the Indian and Western Pacific Oceans, but one species is found in the lakes of the Solomon Islands. Flat-tailed snakes are highly venomous, but rarely bite. Sea snakes have 16 genera and 55 species, for oviparous snakes, completely free from the dependence on land and in the land action difficulties or can not walk. Sea snakes and flat-tailed snakes have similar distribution areas, but the long-snouted sea snake Pelamis platurus (below left) is not confined to the sea, but can live in the ocean, so it is very widely distributed, not only in the tropical waters of the Indian Ocean and the western Pacific Ocean, but also as far away as the eastern Pacific Ocean up to the coasts of the Americas, and they are the most abundant snakes in the world.
(3)Viperidae
Viperidae has 28~34 genera and 220~250 species, it is a venomous snake with tube fangs, the fangs are huge and can be folded and retracted, it is the most progressive snake. Members of the Viperidae family are distinctly different from other snakes in size, with short, thick bodies, short, suddenly thin tails, large, triangular heads, and, in some species, infrared-sensitive cheek sockets. The family Viperidae can be divided into three subfamilies, Viperinae, a subfamily of vipers without cheek sockets, Crotalinae, a subfamily of pit vipers with cheek sockets, and Azemiopinae, a primitive and enigmatic subfamily of white-headed vipers, which are sometimes upgraded to separate families. The subfamily Viperidae consists of about 70 species in 12-13 genera and is widely distributed throughout Eurasia and Africa. The subfamily Viperidae includes the most northerly-distributed vipers, of which the extreme northern viper, Vipera berus, is found throughout northern Eurasia and is the only viper seen in the United Kingdom as far north as the Arctic tundra. The subfamily Vipera berus includes some of the largest venomous snakes with fangs, such as the African Gabon Sizzling Viper, Bitis gabonica, which has fangs up to 5 centimeters long. The Gabon sibilant viper is also one of the largest and best-known vipers in Africa, with a very robust body, and is among the most intricately patterned snakes, along with its close relative, the rhinoceros sibilant viper, Bitis nasicornis (pictured right). The subfamily White-headed Viper is represented only by the White-headed Viper Azemiops fea (pictured). The white-headed viper is the most primitive member of the family Viperidae, and is very rare and poorly known in Myanmar and southern China. All other members of the Viperidae family belong to the subfamily Pitvipers, a highly successful subfamily that is widely distributed, on every continent except Australia, and is the dominant venomous snake in most areas. The most famous of the subfamily is the rattlesnake Crotalus, known for its tail that emits an audible alarm and can sense infrared light. Rattlesnakes are primarily found in North America, but three species are found in Central and South America. The eastern diamondback rattlesnake Crotalus adamanteus of the southeastern United States is over 2 meters long and is the largest and heaviest viper in North America. The giant pit viper Lachesis muta of South and Central America is larger than the eastern diamondback rattlesnake, with a length of nearly 4 meters, making it the largest viper in the Western Hemisphere, as well as the largest pit viper and heaviest viper in the world. There are many species of pit vipers in Asia, of which members of the pit viper genus Agkistrodon and the branded iron head genus Trimeresurus are the most common venomous snakes in our country and the main venomous snakes that bite people in our country.