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Colubridae (/kəˈlbrɪd/, commonly known as colubrids /ˈkɒljʊbrɪdz/, from Latin: coluber, 'snake') is a family of snakes. With 249 genera,[2] it is the largest snake family. The earliest fossil species of the family date back to the Late Eocene epoch, with earlier origins suspected.[1] Colubrid snakes are found on every continent except Antarctica.[3]

Colubridae
Temporal range: Late Eocene—present [1]
Colubridae species
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Superfamily: Colubroidea
Family: Colubridae
Oppel, 1811

Description

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Colubrids are a very diverse group of snakes. They can exhibit many different body styles, body sizes, colors, and patterns. They can also live in many different types of habitats including aquatic, terrestrial, semi-arboreal, arboreal, desert, mountainous forests, semi-fossorial, and brackish waters.[4]: 622–623  A primarily shy and harmless group of snakes, the vast majority of colubrids are not venomous, nor do most colubrids produce venom that is medically significant to mammals. However, the bites of a few groups (such as Boiga sp.) can escalate quickly to emergency situations. Furthermore, within the Colubridae, the South African boomslang and twig snakes, as well as the Asian keelback snakes (Rhabdophis sp.) have long been notorious for inflicting the worst bites on humans, with the most confirmed fatalities.[3][5][6]

Some colubrids are described as opisthoglyphous (often simply called "rear-fanged"), meaning they possess shortened, grooved "fangs" located at the back of the upper jaw. It is thought that opisthoglyphy evolved many times throughout the natural history of squamates[5] and is an evolutionary precursor to the larger, frontal fangs of vipers and elapids.[7][8][9][3][5] These grooved fangs tend to be sharpest on the anterior and posterior edges.[10] While feeding, colubrids move their jaws backward to create a cutting motion between the posterior edge and the prey's tissue.[10] In order to inject venom, colubridae must chew on their prey.[11] Colubrids can also be proteroglyphous (fangs at the front of the upper jaw, followed by small solid teeth)[4]

Most Colubridae are oviparous (mode of reproduction where an egg is produced that will later hatch) with clutch size varying by size and species of snake. However, certain species of snakes from the subfamilies of Natricinae and Colubrinae are viviparous (mode of reproduction where young are live birthed). These viviparous species can birth various amounts of offspring at a time, but the exact number of offspring depends on the size and species of snake.[4]

Characteristics of Colubridae

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Characteristics of Colubridae include limbless bodies, left lung that is reduced or absent with or without a tracheal lung, well-developed oviducts, premaxillaries that lack teeth, maxilaries oriented longitudinally with teeth that are solid or grooved, mandible without a coronoid bone, dentary that has teeth, only a left carotid artery, intracostal arteries arising from the dorsal aorta every few trunk segments, no cranial infrared receptors occurring in pits or surface indentations, and optic foramina that typically traverse the frontal–parietal–parasphenoid sutures.[4]

Classification

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In the past, the Colubridae were not a natural group, as many were more closely related to other groups, such as elapids, than to each other.[12] This family was historically used as a "wastebasket taxon"[6] for snakes that do not fit elsewhere.[13] Until recently, colubrids were basically colubroids that were not elapids, viperids, or Atractaspis.[14]

However, recent research in molecular phylogenetics has stabilized the classification of historically "colubrid" snakes and the family as currently defined is a monophyletic clade,[15][16][17][18] although additional research will be necessary to sort out all the relationships within this group. As of May 2018, eight subfamilies are recognized.[19]

Current subfamilies

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Sibynophiinae – three genera

Natricinae – 36 genera (sometimes given as family Natricidae)

 
Two Indian rat snakes (grey and yellow)
 
A natricine, Thamnophis sirtalis

Pseudoxenodontinae – two genera

Dipsadinae – over 100 genera (sometimes given as family Dipsadidae)

 
A dipsadine, Sibon longifrenis

Grayiinae – one genus

Calamariinae – seven genera

Ahaetuliinae – five genera

Colubrinae – 93 genera

 
A colubrine, Dolichophis jugularis, preying on a legless lizard, a sheltopusik

Sub-family currently undetermined

Former subfamilies

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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.

Fossil record

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The oldest colubrid fossils are indeterminate vertebrae from Thailand and specimens of the genus Nebraskophis from the U.S. state of Georgia, both from the Late Eocene. The presence of derived colubrids in North America so early on, despite their presumed Old World origins, suggests that they originated even earlier.[1] The Pliocene (Blancan) fossil record in the Ringold Formation 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.[24]

References

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Citations

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  1. ^ a b c P Dennis; A J (2003). Nebraskophis HOLMAN from the Late Eocene of Georgia (USA), the oldest known North American colubrid snake.
  2. ^ "Colubrid". britannica.com. Britannica. Archived from the original on 3 December 2018. Retrieved 2 December 2018.
  3. ^ a b c Bauer, Aaron M. [in French] (1998). Cogger, H.G.; Zweifel, R.G. (eds.). Encyclopedia of Reptiles and Amphibians. San Diego: Academic Press. pp. 188–195. ISBN 978-0-12-178560-4.
  4. ^ a b c d Vitt, Laurie J.; Caldwell, Janalee P. (2013). Herpetology: An Introductory Biology of Amphibians and Reptiles (4th ed.). Elsevier Inc. pp. 622–626. ISBN 978-0-12-386919-7.
  5. ^ a b c Bruna Azara, C. (1995). "Animales venenosos. Vertebrados terrestres venenosos peligrosos para el ser humano en España" (PDF). Boletín de la S.E.A. 11: 32–40. Archived (PDF) from the original on 2020-08-14. Retrieved 2016-09-30.
  6. ^ a b "Venomous" Bites from Non-Venomous Snakes. 2011. doi:10.1016/C2010-0-68461-6. ISBN 978-0-12-387732-1.
  7. ^ Jackson, K (2003). "The evolution of venom-delivery systems in snakes". Zoological Journal of the Linnean Society. 137 (3): 337–354. doi:10.1046/j.1096-3642.2003.00052.x.
  8. ^ Vonk, F. J.; Admiraal, J. F.; Jackson, K.; Reshef, R.; de Bakker, M. A.; Vanderschoot, K.; van den Berge, I.; van Atten, M.; Burgerhout, E.; Beck, A. (2008). "Evolutionary origin and development of snake fangs". Nature. 454 (7204): 630–633. Bibcode:2008Natur.454..630V. doi:10.1038/nature07178. PMID 18668106. S2CID 4362616.
  9. ^ Fry, B. G.; Casewell, N. R.; Wüster, W.; Vidal, N.; Young, B.; Jackson, T. N. (2012). "The structural and functional diversification of the Toxicofera reptile venom system". Toxicon. 60 (4): 434–448. Bibcode:2012Txcn...60..434F. doi:10.1016/j.toxicon.2012.02.013. PMID 22446061.
  10. ^ a b Cleuren, Silke G. C.; Hocking, David P.; Evans, Alistair R. (June 2021). "Fang evolution in venomous snakes: Adaptation of 3D tooth shape to the biomechanical properties of their prey". Evolution. 75 (6): 1377–1394. doi:10.1111/evo.14239. PMID 33904594.
  11. ^ Schmalzried, Scott; Ceretto, Vincent (2024). "Snakes". Encyclopedia of Toxicology. pp. 567–571. doi:10.1016/B978-0-12-824315-2.00652-7. ISBN 978-0-323-85434-4.
  12. ^ Lawson, R.; Slowinski, J.B.; Crother, B.I.; Burbrink, F.T. (November 2005). "Phylogeny of the Colubroidea (Serpentes): New evidence from mitochondrial and nuclear genes". Molecular Phylogenetics and Evolution. 37 (2): 581–601. Bibcode:2005MolPE..37..581L. doi:10.1016/j.ympev.2005.07.016. PMID 16172004.
  13. ^ Fry, B.G.; Vidal, N.; van der Weerd, L.; Kochva, E.; Renjifo, C. (2009). "Evolution and diversification of the Toxicofera reptile venom system". Journal of Proteomics. 72 (2): 127–136. doi:10.1016/j.jprot.2009.01.009. PMID 19457354.
  14. ^ Pough, F. Harvey; Cadle, J. E.; Crump, M. L.; Savitzky, A. H.; Wells, K. (1998). Herpetology. Prentice Hall. p. 162. ISBN 978-0-13-850876-0. {{cite book}}: |first2= missing |last2= (help)
  15. ^ Pyron, R. A.; Burbrink, F.; Wiens, J. J. (2013). "A phylogeny and revised classification of Squamata, including 4161 species of lizards and snakes". BMC Evolutionary Biology. 13 (1): 93. Bibcode:2013BMCEE..13...93P. doi:10.1186/1471-2148-13-93. PMC 3682911. PMID 23627680.
  16. ^ Figueroa, A.; McKelvy, A. D.; Grismer, L. L.; Bell, C. D.; Lailvaux, S. P. (2016). "A species-level phylogeny of extant snakes with description of a new colubrid subfamily and genus". PLOS ONE. 11 (9): e0161070. Bibcode:2016PLoSO..1161070F. doi:10.1371/journal.pone.0161070. PMC 5014348. PMID 27603205.
  17. ^ a b c d e f g h Pyron, R. A.; Burbrink, F. T.; Colli, G. R.; de Oca, A. N. M.; Vitt, L. J.; Kuczynski, C. A.; Wiens, J. J. (2011). "The phylogeny of advanced snakes (Colubroidea), with discovery of a new subfamily and comparison of support methods for likelihood trees". Molecular Phylogenetics and Evolution. 58 (2): 329–342. Bibcode:2011MolPE..58..329P. doi:10.1016/j.ympev.2010.11.006. PMID 21074626.
  18. ^ Zheng, Yuchi; Wiens, John J. (January 2016). "Combining phylogenomic and supermatrix approaches, and a time-calibrated phylogeny for squamate reptiles (lizards and snakes) based on 52 genes and 4162 species". Molecular Phylogenetics and Evolution. 94 (Pt B): 537–547. Bibcode:2016MolPE..94..537Z. doi:10.1016/j.ympev.2015.10.009. PMID 26475614.
  19. ^ Uetz, Peter. "Colubridae at The Reptile Database". The Reptile Database. EMBL. Archived from the original on 29 June 2018. Retrieved 13 May 2018.
  20. ^ "Blythia reticulata". Archived from the original on 2021-05-21. Retrieved 2021-05-21.
  21. ^ a b Holman, J. Alan (1982-01-01). "New Herpetological Species and Records from the Norden Bridge Fauna (Miocene: Late Barstovian) of Nebraska". Transactions of the Nebraska Academy of Sciences and Affiliated Societies.
  22. ^ "Floridaophis auffenbergi". Florida Vertebrate Fossils. Retrieved 2023-12-15.
  23. ^ a b Savage, Jay M. (2015). "What are the correct family names for the taxa that include the snake genera Xenodermus, Pareas, and Calamaria?". Herpetological Review. 46 (4): 664–665. Archived from the original on 2016-03-07. Retrieved 2018-05-14.
  24. ^ Parmley, D.; Walker, D. (2003). "Snakes of the Pliocene Taunton local fauna of Adams County, Washington with the description of a new colubrid". Journal of Herpetology. 37 (2): 235–244. doi:10.1670/0022-1511(2003)037[0235:SOTPTL]2.0.CO;2. S2CID 86000331.

Bibliography

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