A colubrid is a member of the snake

Snake

Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...

 family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Colubridae. This broad classification of snakes includes about two-thirds of all snake species on earth. The earliest species of the snake family date back to the Oligocene

Oligocene

The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...

 epoch. With 304 genera and 1,938 species, Colubridae is the largest snake family. Colubrid species are found on every continent except Antarctica.

Description

While most colubrids are nonvenomous (or have venom that is not known to be harmful to humans) and are mostly harmless, a few groups, such as genus Boiga

Boiga

Boiga is a large genus of mildly venomous, rear-fanged, colubrid snakes typically known as the cat-eyed snakes or just cat snakes. They are primarily found throughout southeast Asia, India and Australia, but due to their extremely hardy nature and adaptability have spread to many other suitable...

, can produce medically significant bites, while the boomslang

Boomslang

The boomslang is a large venomous colubrid snake.-Taxonomy & etymology:It is currently the only species in its genus, although several species and subspecies have been described in the past...

, the twig snake

Twig snake

The twig or bird snakes of the genus Thelotornis are a group of back-fanged, colubrid snakes in the family Colubridae. All species have a slender and elongated profile, a long tail, narrow head and pointed snout. The eyes of each species have horizontal pupils, shaped like keyholes, which gives...

s and the Asian genus Rhabdophis

Rhabdophis

Rhabdophis is a genus of snakes, generally called keelback snakes, found primarily in southeast Asia.- Species of Rhabdophis :* Rhabdophis adleri* Rhabdophis angeli* Rhabdophis auriculata...

have caused human fatalities.

Some of the colubrids are described as opisthoglyphous, meaning they have elongated, grooved teeth located in the back of the upper jaw. The opisthoglyphous dentition appears at least two times in the history of snakes. These are unlike those of vipers

Viperidae

The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...

 and elapids, which are located in the front.

Classification

The Colubridae are not a natural group

Monophyly

In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...

, as many are more closely related to other groups, such as elapids

Elapidae

Elapidae is a family of venomous snakes found in tropical and subtropical regions around the world, terrestrially in Asia, Australia, Africa, North America and South America and aquatically in the Pacific and Indian Oceans...

, than to each other. This family has classically been a garbage bin taxon for snakes that do not fit elsewhere. Ongoing research, hopefully, will sort out the relations within this group.

Subfamily Boodontinae

• Bothrolycus
  Bothrolycus
  Günther's Black Snake, Bothrolycus ater, is a species of poorly-known colubrid snake endemic to central Africa. It is the only member of the genus, Bothrolycus. This snake is notable as one of the few snakes with notable sexual dimorphism , as well as possessing a small pit anterior to the eye...
  
  
• Bothrophthalmus
  Bothrophthalmus
  The Red-Black Striped Snake or, Bothrophthalmus lineatus, is the monotypical member of the genus Bothrophthalmus. This snake is found in the East African counrys of Rwanda, Uganda, Burundi, Angola, Guinea. It is a harmless snake, black with 5 red striped down the back. It lives n forests and...
  
  
• Buhoma (tentatively placed here)
• Chamaelycus
  Chamaelycus
  Chamaelycus is a genus of colubrid snakes commonly referred to as banded snakes.There are four commonly accepted species in the genus Chamaelycus:*Christy's Banded Snake - Chamaelycus christyi*African Banded Snake - Chamaelycus fasciatus...
  
  
• Dendrolycus
  Dendrolycus
  The Cameroon Rainforest Snake or Dendrolycus elapoides is a species of colubrid snake. It is monotypical of the genus, Dendrolycus....
  
  
• Dipsina
  Dipsina
  The Dwarf Beaked Snake, Dipsina multimaculata, is a colubrid snake. It is also known as the Western Beaked Snake. The Dwarf Beaked Snake is in the monotypic genus Dipsina....
  
  
• Dromophis
  Dromophis
  Dromophis is a genus of colubrid snakes. There are two commonly accepted species in the genus Dromophis:*Lined Olympic Snake - Dromophis lineatus Dumeril, Bibron & Dumeril 1854...
  
  
• Duberria (tentatively placed here)
• Gonionotophis
  Gonionotophis
  Gonionotophis is a genus of colubrid snakes also known as the African Ground Snakes & File Snakes. As of November 2010, there are 15 recognized species in the genus:* Mocquard's African Ground Snake, Gonionotophis brussauxi...
  
  
• Grayia
• Hormonotus
  Hormonotus
  Hormonotus is a genus of colubrid snakes. At present this genus is monotypic, as there is only one commonly accepted species in it, the Uganda house snake...
  
  
• Lamprophis
  Lamprophis
  Lamprophis is a genus of colubrid snakes commonly referred to as African house snakes. They are small, non-venomous snakes. They exhibit a wide variety of pattern variation, and may be spotted, striped, or solid colored...
  
  
• Lycodonomorphus
  Lycodonomorphus
  Lycodonomorphus is a genus of colubrid snakes commonly referred to as African water snakes. They are small, non-venomous snakes with all members being endemic to Africa, especially Tanzania.-Species:* Lycodonomorphus bicolor...
  
  
• Lycophidion
  Lycophidion
  Lycophidion is a genus of colubrid snakes commonly referred to as the Wolf snakes.The genus contains the following species:*Lycophidion meleagris*Lycophidion acutirostre*Lycophidion laterale*Lycophidion semiannulis...
  
  
• Macroprotodon
  Macroprotodon
  Macroprotodon is a genus of snakes in the Colubridae family. All of the members of the genus are commonly known as false smooth snakes.It contains the following species:* Macroprotodon abubakeri* Macroprotodon brevis...
  
  
• Mehelya
  Mehelya
  Mehelya is a genus of colubrid snakes from Africa. They are collectively grouped as file snakes due to their unusual scalation. They are nonvenomous.- Species :There are 10 recognized species within the genus Mehelya:...
  
  
• Montaspis (tentatively placed here)
• Pseudaspis
• Pseudoboodon
• Pythonodipsas
• Scaphiophis

Subfamily Calamariinae

Calamariinae

Calamariinae is a subfamily of colubrid snakes which are found throughout Asia. It contains seven genera.-Genera:*Calamaria *Calamorhabdium *Collorhabdium*Etheridgeum*Macrocalamus*Pseudorabdion...

• Calamaria
  Calamaria
  Calamaria is a large genus of dwarf snakes of the family Colubridae. It contains sixty recognized species.-Description:Species in the genus Calamaria share the following characteristics. Maxillary teeth 8-11, subequal; anterior mandibular teeth a little longer than the posterior...
  
  
• Calamorhabdium
  Calamorhabdium
  Calamorhabdium is a small genus of colubrid snakes known as iridescent snakes. The genus contains two described species. Both species are burrowing snakes found in Asia.-Species:*Calamorhabdium acuticeps Ahl, 1933; Sulawesi iridescent snake...
  
  
• Collorhabdium
• Etheridgeum
• Macrocalamus
• Pseudorabdion
• Rabdion

Subfamily Colubrinae

Colubrinae

Colubrinae is a subfamily of the Colubridae family of snakes. It includes numerous genera, and taxonomic sources often disagree on the exact number...

- nearly 100 genera

Subfamily Dipsadinae

• Adelphicos
  Adelphicos
  The genus Adelphicos consists of six species of Burrowing Snake.-Geographic range:These snakes can be found in the Central American subcontinent, mostly in Mexico, Belize, and Guatemala.- Species :...
  
  
• Amastridium
• Atractus
  Atractus
  Ground Snakes are a genus of colubrid snakes that belong to the Xenodontinae subfamily. The genus includes more than 80 distinct species.-Geographic range:...
  
  
• Calamodontophis
  Calamodontophis
  Calamodontophis is a genus of snake in the Colubridae family.It is found in Brazil and Uruguay and contains the following species:* Calamodontophis paucidens * Calamodontophis ronaldoi...
  
  (tentatively placed here)
• Carphophis
  Carphophis
  Carphophis is a genus of small colubrid snakes. The genus consists of two species.- Physical description :...
  
  (tentatively placed here)
• Chersodromus
• Coniophanes
  Coniophanes
  Coniophanes is a large genus of colubrid snakes, typically referred to as black-striped snakes, but they also have many other common names...
  
  
• Contia (tentatively placed here)
• Crisantophis (tentatively placed here)
• Cryophis
• Diadophis (tentatively placed here)
• Diaphorolepsis (tentatively placed here)
• Dipsas
  Dipsas
  Dipsas is a genus of non-venomous colubrid snakes that belong to the Xenodontinae subfamily. It is found from southern Mexico through Central America and South America, as far as Argentine and Paraguay.The genus includes over 30 distinct species....
  
  
• Echinanthera (tentatively placed here)
• Emmochliophis (tentatively placed here)
• Enuliophis (tentatively placed here)
• Enulius (tentatively placed here)
• Eridiphas
• Geophis
  Geophis
  Geophis is a genus of colubrid snakes that belong to the Xenodontinae subfamily and are typically referred to as Latin American earth snakes...
  
  
• Gomesophis (tentatively placed here)
• Hydromorphus (tentatively placed here)
• Hypsiglena
  Hypsiglena
  Hypsiglena is a genus of small, rear-fanged, colubrid snakes commonly referred to as night snakes. The genus consists of two distinct species, many subspecies may be considered synonymous depending on the source.- Species :...
  
  
• Imantodes
• Leptodeira
  Leptodeira
  Leptodeira is a genus of colubrid snakes commonly referred to as cat-eyed snakes. The genus consists of 10 species that are native to primarily Mexico and Central America, but range as far north as the southern tip of Texas in United States and as far south as Argentina in South America.- Species...
  
  
• Ninia
  Ninia
  Ninia is a genus of colubrid snakes commonly referred to as Coffee snakes. The genus consists of 8 species that are native to Mexico, Central America, and the northern part of South America. Some species are also found on the Caribbean islands....
  
  
• Nothopsis (tentatively placed here)
• Pliocercus
• Pseudoleptodeira
• Pseudotomodon (tentatively placed here)
• Ptychophis (tentatively placed here)
• Rhadinaea
• Rhadinophanes (tentatively placed here)
• Sibon
• Sibynomorphus
• Synophis (tentatively placed here)
• Tachymenis
  Tachymenis
  Tachymenis is a genus of venomous snakes belonging to the family Colubridae. They are commonly known as slender snakes or short-tailed snakes and are primarily found in southern South America. Tachymenis are capable of producing a medically significant bite, with at least one species, T...
  
  (tentatively placed here)
• Taeniophallus (tentatively placed here)
• Tantalophis (tentatively placed here)
• Thamnodynastes (tentatively placed here)
• Tomodon
  Tomodon
  Tomodon is a genus of colubrid snakes. Two species are currently recognized.* Tomodon dorsatus - Duméril, Bibron and Duméril, 1854 * Tomodon ocellatus - Duméril, Bibron and Duméril, 1854...
  
  (tentatively placed here)
• Tretanorhinus
• Trimetopon
• Tropidodipsas
• Urotheca
• Xenopholis (tentatively placed here)

Subfamily Homalopsinae

Homalopsinae

Homalopsinae is a subfamily of Colubridae which contains some 10 genera and about 4 dozen species. They are typically stout-bodied water snakes, and all are mildly venomous. The genus Brachyorrhos may belong elsewhere...

- about 10 genera

Subfamily Natricinae

Natricinae

Natricinae is a subfamily of the colubrid family of snakes which contains 28 genera. Members of this subfamily include many very common snake species, such as the European Grass Snakes, and the North American Water Snakes.- Genera :...

- about 30 genera

Subfamily Pareatinae

Pareatinae

Pareatinae is a small subfamily of the Colubridae family of snakes. It encompasses a mere 3 genera, which include snakes that eat snails....

- three genera

Subfamily Psammophiinae

• Hemirhagerrhis
• Malpolon
• Mimophis
• Psammophis
  Psammophis
  Psammophis is a genus of colubrid snakes.-Description:Maxillary teeth 10 to 13, one or two in the middle much enlarged and fang-like, preceded and followed by an interspace, the two posterior grooved. Anterior mandibular teeth long, posterior small. Head elongate and distinct from neck, with...
  
  
• Psammophylax
• Rhamphiophis

Subfamily Pseudoxenodontinae

• Plagiopholis
• Pseudoxenodon

Subfamily Pseudoxyrhophiinae

Pseudoxyrhophiinae

Pseudoxyrhophiinae is a subfamily of colubrid snakes.It contains about 20 genera:* Alluaudina* Bibilava * Brygophis* Compsophis* Ditypophis* Dromicodryas* Exallodontophis...

- about 20 genera

Subfamily Xenodermatinae

• Achalinus
  Achalinus
  Achalinus is a genus of harmless colubrid colubrid snakes found in Japan, Taiwan, China and northern Vietnam. Nine species are currently recognized.-Species:*) Not including the nominate subspecies....
  
  
• Fimbrios
• Oxyrhabdium
• Stoliczkaia
• Xenodermus
  Xenodermus
  Xenodermus is a genus of colubrid snakes. It is a monotypic genus, containing only Xenodermus javanicus....
  
  
• Xylophis

Subfamily Xenodontinae

Xenodontinae

Xenodontinae is a subfamily of the Colubridae family of snakes. It encompasses a number of genera, which include species such as mud snakes and New World hognose snakes.- Genera :Other genera are often placed here but may actually belong elsewhere:...

- some 55-60 genera

incertae sedis

Incertae sedis

, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...

• Blythia
• Cercaspis
• Cyclocorus
  Cyclocorus
  Cyclocorus is a genus of colubrid snakes.-Species and subspecies:The following species and subspecies have been described.Cyclocorus lineatus , Reinhardt's Lined Snake* C. l. alcalai Leviton, 1967...
  
  
• Elapoidis
• Gongylosoma
• Haplocercus
• Helophis
• Myersophis
• Omoadiphas (recently discovered)
• Oreocalamus
• Poecilopholis
  Poecilopholis
  Poecilopholis is a monotypic genus created for the fangless venomous snake species, Poecilopholis cameronensis, which is endemic to Africa.-Geographic range:As the specific name implies, Poecilopholis cameronensis is found in Cameroon....
  
  
• Rhabdops
• Tetralepis
• Thermophis
  Thermophis
  Thermophis is a genus of snakes in the family Colubridae.-Species:The genus includes two species:* Thermophis baileyi - Bailey's snake, hot-spring keel-back, Xizang hot-spring keel-back...
  
  
• Trachischium
  Trachischium
  Trachischium is a genus of colubrid snakes commonly known as worm-eating snakes.-Geographic range:They are found through montane regions of the countries of Nepal, India, Bangladesh, Bhutan and China.-Description:...