Colubridae (, commonly known as colubrids , from la, coluber, 'snake') is a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...

s. With 249

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

, it is the largest snake family. The earliest species of the family date back to the

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

epoch. Colubrid snakes are found on every continent except Antarctica.

Description

While most colubrids are not

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

ous (or have venom that is not known to be harmful to humans) and are mostly harmless, a few groups, such as genus ''

Boiga ''Boiga'' is a large genus of rear-fanged, mildly venomous snakes, known commonly as cat-eyed snakes or simply cat snakes, in the family Colubridae. Species of the genus ''Boiga'' are native to southeast Asia, India, and Australia, but due t ...

'', can produce medically significant injuries. In addition, the boomslang, the

twig snake The twig snakes (genus ''Thelotornis''), also commonly known as bird snakes or vine snakes, are a genus of rear-fanged venomous snakes in the family Colubridae. The genus is native to Africa. All species in the genus have a slender and elonga ...

s, and the Asian genus ''

Rhabdophis ''Rhabdophis'' is a genus of snakes in the subfamily Natricinae of the family Colubridae. Species in the genus ''Rhabdophis'' are generally called keelback snakes, and are found primarily in Southeast Asia. Toxicity ''Rhabdophis'' is often thou ...

'' have caused human fatalities. Some colubrids are described as

opisthoglyphous A snake skeleton consists primarily of the skull, vertebrae, and ribs, with only vestigial remnants of the limbs. Skull The skull of a snake is a very complex structure, with numerous joints to allow the snake to swallow prey far larger than it ...

(often called "rear-fanged"), meaning they have elongated, grooved teeth located in the back of their upper jaws. It is likely that opisthoglyphous dentition evolved many times in the history of snakes and is an evolutionary precursor to the fangs of

vipers The Viperidae (vipers) are a family of snakes found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, and various other isolated islands. They are venomous and have long (relative to non-vipers), hinged fangs th ...

and

elapids Elapidae (, commonly known as elapids ; grc, ἔλλοψ ''éllops'' "sea-fish") is a family of snakes characterized by their permanently erect fangs at the front of the mouth. Most elapids are venomous, with the exception of the genus Emydocep ...

, which are located in the front of the mouth.

Classification

In the past, the Colubridae were not a natural group, as many were more closely related to other groups, such as

, than to each other. This family was historically used as a "

wastebasket taxon Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the sole purpose of classifying organisms that do not fit anywhere else. They are typically defined ...

" for snakes that do not fit elsewhere. Until recently, colubrids were basically colubroids that were not

viperids The Viperidae (vipers) are a family of snakes found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, and various other isolated islands. They are venomous and have long (relative to non-vipers), hinged fangs t ...

, or '' Atractaspis''. However, recent research in molecular phylogenetics has stabilized the classification of historically "colubrid" snakes and the family as currently defined is a

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

, although additional research will be necessary to sort out all the relationships within this group. As of May 2018, eight subfamilies are recognized.

Current subfamilies

Sibynophiinae Sibynophiinae is a small subfamily of colubroid snakes, sometimes referred to as a family (Sibynophiidae). This group has also been called Scaphiodontophiinae but since the name Sibynophiinae is older, it has priority. They are commonly called h ...

– two genera

Natricinae The Natricinae are a subfamily of colubroid snakes, sometimes referred to as a family (Natricidae). The subfamily comprises 37 genera. Members include many very common snake species, such as the European grass snakes, and the North American wa ...

– 36 genera (sometimes given as family

Natricidae The Natricinae are a subfamily of colubroid snakes, sometimes referred to as a family (Natricidae). The subfamily comprises 37 genera. Members include many very common snake species, such as the European grass snakes, and the North American ...

)

Pseudoxenodontinae Pseudoxenodontinae is a small subfamily of colubroid snakes, sometimes referred to as a family (Pseudoxenodontidae). They are found in southern and southeastern Asia, from northeast India to southern China (including Taiwan) and south into Indo ...

– two genera

Dipsadinae 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. Dips ...

– 100 genera (sometimes given as family Dipsadidae) Grayiinae – one genus *'' Grayia'' Calamariinae – seven genera Ahaetuliinae – five genera

Colubrinae 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 t ...

– 94 genera

Former subfamilies

These taxa have been at one time or another classified as part of the Colubridae, but are now either classified as parts of other families, or are no longer accepted because all the species within them have been moved to other (sub)families. *Subfamily Aparallactinae (now a subfamily of

Lamprophiidae The Lamprophiidae are a family of snakes found throughout much of Africa, including the Seychelles. There are 89 species as of July 2022. Biology Lamprophiids are a very diverse group of snakes. Many are terrestrial but some are fossorial (e.g. ...

, sometimes combined with Atractaspidinae) *Subfamily Boiginae (now part of

) *Subfamily

Boodontinae Boodontinae is a subfamily of colubrid snakes. Genera It contains 22 genera. *'' Boaedon'' *'' Bothrolycus'' *'' Bothrophthalmus'' *'' Buhoma'' *'' Chamaelycus'' *''Dendrolycus'' *'' Dipsina'' *'' Dromophis'' *'' Duberria'' *'' Gonionotophis'' ...

(some of which now treated as subfamily Grayiinae of the new Colubridae, others moved to family

as part of subfamilies Lamprophiinae,

Pseudaspidinae Pseudaspididae is a small family (biology), family of Elapoidea, elapoid snakes. They were formerly placed as a subfamily of the Lamprophiidae, but have been more recently identified as a distinct family. They have a disjunct distribution; two ...

and

Pseudoxyrhophiidae The Pseudoxyrhophiidae is a family of elapoid snakes, found mostly in Madagascar. They were formerly placed as a subfamily of the Lamprophiidae, but have been more recently identified as a distinct family. It contains about 22 genera in two s ...

, which are now sometimes treated as families) *Subfamily Dispholidinae (now part of Colubrinae) *Subfamily

Homalopsinae The Homalopsidae are a family of snakes which contains about 28 genera and more than 50 species. They are commonly known as Indo-Australian water snakes, mudsnakes, or bockadams. They are also known as ''ular air'' (lit. "water snake") in Indon ...

(now family Homalopsidae) *Subfamily Lamprophiinae (now a subfamily of Lamprophiidae) *Subfamily Lycodontinae (now part of Colubrinae) *Subfamily Lycophidinae (now part of Lamprophiidae) *Subfamily Pareatinae (now family

Pareidae Pareidae is a small family of snakes found largely in southeast Asia, with an isolated subfamily endemic to southwestern India. It encompasses 42 species in four genera divided into two subfamilies: Pareinae and Xylophiinae. Both families are tho ...

, sometimes incorrectly spelled Pareatidae) *Subfamily Philothamninae (now part of Colubrinae) *Subfamily Psammophiinae (now a subfamily of Lamprophiidae) *Subfamily

Pseudoxyrhophiinae The Pseudoxyrhophiidae is a Family (biology), family of Elapoidea, elapoid Lamprophiidae, snakes, found mostly in Madagascar. They were formerly placed as a subfamily of the Lamprophiidae, but have been more recently identified as a distinct fami ...

(now a subfamily of Lamprophiidae) *Subfamily Xenoderminae (now family

Xenodermidae Xenodermidae is a family of snakes native to East Asia, South Asia, and Southeast Asia. All species in the family Xenodermidae are small or moderately sized snakes, never more than but typically less than in total length (including tail). They ...

, sometimes incorrectly spelled Xenodermatidae) *Subfamily

Xenodontinae Xenodontinae is a subfamily of snakes in the family Colubridae. The subfamily Xenodontinae encompasses a number of rear-fanged (opisthoglyphous), mildly venomous snake genera found in South America and the Caribbean. Members of the subfamily ...

(which many authors put in

/ Dipsadidae)

Fossil record

The Pliocene ( Blancan) fossil record in the

Ringold Formation The Ringold Formation is a geologic formation in Eastern Washington, United States. The formation consists of sediment laid down by the Columbia River following the flood basalt eruptions of the Columbia River Basalt Group, and reaches up to thi ...

of Adams County, Washington has yielded fossils from a number of colubrids including '' Elaphe pliocenica'', '' Elaphe vulpina'', '' Lampropeltis getulus'', '' Pituophis catenifer'', a '' Thamnophis'' species, and the extinct genus '' Tauntonophis''.

References

Citations

Bibliography

* * * * * * * * * * *

External links

Psammophids
at Life Is Short, but Snakes Are Long {{Authority control Cenozoic reptiles Extant Oligocene first appearances Snake families Taxa described in 1881 Taxa named by Nicolaus Michael Oppel