The Boidae, commonly known as boas or boids, are a family of nonvenomous snakes primarily found in the Americas, as well as Africa, Europe, Asia, and some Pacific islands. Boas include some of the world's largest snakes, with the green anaconda of South America being the heaviest and second-longest snake known; in general, adults are medium to large in size, with females usually larger than the males. Six subfamilies comprising 15 genera and 54 species are currently recognized.
Hydrophiinae is a subfamily of venomous snakes in the family Elapidae. It contains most sea snakes and many genera of venomous land snakes found in Australasia, such as the taipans (Oxyuranus), tiger snakes (Notechis), brown snakes (Pseudonaja) and death adders (Acanthophis).
The Caenophidia are a derived clade of alethinophidian snakes, which contains over 80% of all the extant species of snakes. The largest family is Colubridae, but it also includes at least seven other families, at least four of which were once classified as "Colubridae" before molecular phylogenetics helped us understand their relationships. It has been found to be monophyletic.
The Aniliidae are a monotypic family created for the monotypic genus Anilius that contains the single species Anilius scytale. Common names include the American pipe snake and false coral snake. It is found in South America. This snake possesses a vestigial pelvic girdle that is visible as a pair of cloacal spurs. It is ovoviviparous. It is non-venomous, and its diet consists mainly of amphibians and other reptiles. Two subspecies are recognized, including the nominate subspecies described here.
Henophidia is a former superfamily of the suborder Serpentes (snakes) that contains boas, pythons and numerous other less-well-known snakes.
The Natricinae are a subfamily of colubroid snakes, sometimes referred to as a family (Natricidae). The subfamily comprises 36 genera. Members include many very common snake species, such as the European grass snakes, and the North American water snakes and garter snakes. Some Old World members of the subfamily are known as keelbacks, because their dorsal scales exhibit strong keeling.
The Colubrinae are a subfamily of the family Colubridae of snakes. It includes numerous genera, and although taxonomic sources often disagree on the exact number, The Reptile Database lists 717 species in 92 genera as of September 2019. It is the second largest subfamily of colubrids, after Dipsadinae. Many of the most commonly known snakes are members of this subfamily, including rat snakes, king snakes, milk snakes, vine snakes, and indigo snakes.
Madtsoiidae is an extinct family of mostly Gondwanan snakes with a fossil record extending from early Cenomanian to late Pleistocene strata located in South America, Africa, India, Australia and Southern Europe. Madtsoiidae include very primitive snakes, which like extinct boas and pythons would likely dispatch their prey by constriction. Genera include Madtsoia, one of the longest snakes known, at an estimated 10 metres (33 ft), and the Australian Wonambi and Yurlunggur. As a grouping of basal forms the composition and even the validity of Madtsoiidae is in a state of flux as new pertinent finds are described, with more recent evidence suggesting that it is paraphyletic as previously defined.
The Lamprophiidae are a family of snakes found throughout much of Africa, including the Seychelles. There are 89 species as of July 2022.
Colubroidea is a superfamily of snakes in the clade Colubroides that includes Colubridae, with some studies splitting Colubridae into multiple families that make up Colubroidea. Historically, Colubroidea also included other caenophidian snakes such as cobras and vipers, as these snakes form a clade. However these groups are now divided into several distinct, but related, families. Zaher et al. (2009) proposed to redefine Colubroidea for colubrids and related families, while designating Colubroides as the group containing vipers and cobras as well as colubroids. The ReptileDatabase considers Colubroidea to be composed of Colubridae and the members of its sister group, Elapoidea, and does not recognize the division of Colubridae into multiple families.
Dipsadinae is a large subfamily of colubroid snakes, sometimes referred to as a family (Dipsadidae). They are found in most of the Americas, including the West Indies, and are most diverse in South America. There are more than 700 species.
Lamprophiinae is a subfamily of lamprophiid snakes, a large group of mostly African snakes, most of which were formerly classified as colubrids but which we now know are actually more closely related to elapids.
Pseudaspididae is a small family of elapoid snakes. They were formerly placed as a subfamily of the Lamprophiidae, but have been more recently identified as a distinct family.
The Booidea, also known as booid snakes, are a superfamily of snakes that contains boas and other closely related boa-like snakes. As of 2017, Booidea contains 61 species, including the eponymous neotropical Boa constrictor, anacondas, and smaller tree and rainbow boas as well as several genera of booid snakes from various locations around the world: bevel-nosed boas or keel-scaled boas (Candoia) from New Guinea and Melanesia, Old World sand boas (Eryx) from Northeast Africa, the Middle East, and Southwest Asia, rubber boas (Charina) and rosy boas (Lichanura) from North America, neotropical dwarf boas (Ungaliophis) and the Oaxacan dwarf boa (Exiliboa) from Central America, Madagascan boas or Malagasy boas from Madagascar, and the Calabar python (Calabaria) from tropical West-Central Africa.
The Uropeltoidea, also known as uropeltoid snakes, are a superfamily of snakes that contains uropeltids and Asian pipesnakes.
The Amerophidia, also known as amerophidian snakes, are a superfamily of snakes that contains two families: Aniliidae and the boa-like Tropidophiidae.
The Colubroides are a clade in the suborder Serpentes (snakes). It contains over 85% of all the extant species of snakes. The largest family is Colubridae, but it also includes at least six other families, at least four of which were once classified as "Colubridae" before molecular phylogenetics helped in understanding their relationships. It has been found to be monophyletic.
Afrophidia is a clade of alethinophidian snakes comprising the groups Henophidia and Caenophidia, essentially making up the snakes people commonly associate with. The name refers to the deep split between Afrophidia and their sister taxon, Amerophidia, which originated in South American origin, and the afrophidians was recently hypothesized to represent a vicariant event of the breakup of Gondwanan South America and Africa.
The Elapoidea are a superfamily of snakes in the clade Colubroides, traditionally comprising the families Lamprophiidae and Elapidae. Advanced genomic sequence studies, however, have found lamprophiids to be paraphyletic in respect to elapids, and anywhere between four and nine families are now recognized.
