The coral snakes are a large group of elapid snakes that can be subdivided into two distinct groups, Old World coral snakes and New World coral snakes. There are 11 species of Old World coral snake in one genus (Calliophis), and over 65 recognized species of New World coral snakes in three genera (Leptomicrurus, Micruroides, and Micrurus).
North American coloration patterns[edit source | edit]
Coral snakes are most notable for their red, yellow/white, and black colored banding. (However, several nonvenomous species have similar coloration, including the scarlet snake, genus Cemophora, some of the kingsnakes and milk snakes, genus Lampropeltis, and the shovelnose snakes, genus Chionactis.) In some regions, the order of the bands distinguishes between the non-venomous mimics and the venomous coral snakes, inspiring some mnemonics — "Red on yellow, poison fellow; red on black, safe from attack." or "Red touch black, you're OK Jack; Red touch yellow, you're dead fellow". However, this reliably applies only to coral snakes native to North America: Micrurus fulvius (Eastern or common coral snake), Micrurus tener (Texas coral snake), and Micruroides euryxanthus (Arizona coral snake), found in the southern and western United States. Coral snakes found in other parts of the world can have distinctly different patterns, have red bands touching black bands, have only pink and blue banding, or have no banding at all.
Most species of coral snake are small in size. North American species average around 3 feet (91 cm) in length, but specimens of up to 5 feet (150 cm) or slightly larger have been reported. Aquatic species have flattened tails acting as a fin, aiding in swimming.
Behavior[edit source | edit]
Coral snakes vary widely in their behavior, but most are very elusive, fossorial snakes which spend the vast majority of their time buried beneath the ground or in the leaf litter of a rainforest floor, coming to the surface only when it rains or during breeding season. Some species, like Micrurus surinamensis, are almost entirely aquatic and spend most of their lives in slow-moving bodies of water that have dense vegetation.
Like all elapid snakes, coral snakes possess a pair of small fangs to deliver their venom (some coral snakes are rear fanged). These fangs, which are enlarged and hollow, deliver their venom to their prey species, feeding mostly on smaller snakes, lizards, frogs, nestling birds, and rodents, etc. The venom takes time to take full effect.
Coral snakes have a tendency to hold on to a victim when biting, unlike vipers, which have retractable fangs and tend to prefer to strike, letting go immediately. Coral snakes are not aggressive or prone to biting and account for less than one percent of the number of snake bites each year in the United States.
Distribution[edit source | edit]
New World coral snakes exist in the southern range of many temperate U.S. states. Coral snakes are found in scattered localities in the southern coastal plain from North Carolina to Louisiana, including all of Florida. They can be found in pine and scrub oak sandhill habitats in parts of this range but sometimes inhabit hardwood areas and pine flatwoods that undergo seasonal flooding.
There is controversy about the classification of the very similar Texas coral snake as a separate species. Its habitat, in Texas, Louisiana, and Arkansas, is separated from the eastern habitat by the Mississippi River. The coral snake population is most dense in the southeast United States, but coral snakes have been spotted as far north as Kentucky.
The Arizona coral snake, clearly a separate species and genus, is found in central and southern Arizona, extreme southwestern New Mexico and southward to Sinaloa in western Mexico. It occupies arid and semiarid regions in many different habitat types including thornscrub, desert-scrub, woodland, grassland and farmland. It is found in the plains and lower mountain slopes from sea level to 5800 feet (1768 m); often found in rocky areas.
Danger to humans[edit source | edit]
New World coral snakes possess one of the most potent venoms of any North American snake. However, relatively few bites are recorded due to their reclusive nature and the fact they generally inhabit sparsely populated areas. According to the American National Institutes of Health, there are an average of 15–25 coral snake bites in the United States each year.
When confronted by humans, coral snakes will almost always attempt to flee, and bite only as a last resort. In addition, coral snakes have short fangs (proteroglyph dentition) that cannot penetrate thick leather clothing. Any skin penetration however, is a medical emergency that requires immediate attention. Coral snakes have a powerful neurotoxin that paralyzes the breathing muscles; mechanical or artificial respiration, along with large doses of antivenom, are often required to save a victim's life. There is usually only mild pain associated with a bite, but respiratory failure can occur within hours.
The bite of a coral snake may soon be more dangerous, in part because bites are so uncommon. Production of coral snake antivenom in the United States has ceased because it is not profitable. According to Pfizer, the owner of the company that used to make Coralmyn, it would take over $5–$10 million to put toward researching a new synthetic antivenom.[clarification needed] The cost was too large for the small number of cases presented each year. The current antivenom stock expired in 2010, after two consecutive expiration date extensions approved by the U.S. Food and Drug Administration. Foreign pharmaceutical manufacturers have produced other coral snake antivenoms, but the costs associated with licensing them in the United States have stalled availability (see above). Instituto Bioclon is developing a coral snake antivenom.
Old World[edit source | edit]
Genus Calliophis[edit source | edit]
|Wikispecies has information related to: Calliophis|
Species in this genus are:
- Calliophis beddomei M.A. Smith, 1943– Beddome's coral snake
- Calliophis bibroni (Jan, 1858) – Bibron's coral snake
- Calliophis bivirgatus (F. Boie, 1827)– blue Malaysian coral snake
- Calliophis gracilis Gray, 1835 – spotted coral snake (Thailand, Malaysia, Indonesia, Singapore)
- Calliophis haematoetron E.N. Smith, Manamendra-Arachchi & Somweera, 2008 – blood-bellied coral snake (Sri Lanka)
- Calliophis intestinalis (Laurenti, 1768) – banded Malaysian coral snake (Indonesia and Malaysia)
- Calliophis maculiceps (Günther, 1858) – speckled coral snake (Myanmar, Thailand, Malaysia, Vietnam, Cambodia, Laos)
- Calliophis melanurus (Shaw, 1802)– Indian coral snake
- Calliophis nigrescens (Günther, 1862)– black coral snake
New World[edit source | edit]
Genus Leptomicrurus[edit source | edit]
Genus Micruroides[edit source | edit]
|Wikispecies has information related to: Micruroides|
- Micruroides euryxanthus (Kennicott, 1860) – Arizona coral snake (lowland regions from Arizona to Sinaloa, Mexico)
Genus Micrurus[edit source | edit]
|Wikispecies has information related to: Micrurus|
- Micrurus alleni K.P. Schmidt, 1936 – Allen's coral snake (eastern Nicaragua, Costa Rica, and Panama)
- Micrurus altirostris (Cope, 1860) (Brazil, Uruguay, and northeastern Argentina)
- Micrurus ancoralis (Jan, 1872) - regal coral snake (southeastern Panama, western Colombia, and western Ecuador)
- Micrurus annellatus (W. Peters, 1871) – annellated coral snake (southeastern Ecuador, eastern Peru, Bolivia, and western Brazil)
- Micrurus averyi K.P. Schmidt, 1939 - black-headed coral snake
- Micrurus bernadi (Cope, 1887) (Mexico)
- Micrurus bocourti (Jan, 1872) – Ecuadorian coral snake (western Ecuador to northern Colombia)
- Micrurus bogerti Roze, 1967 – Bogert's coral snake (Oaxaca)
- Micrurus browni K.P. Schmidt & H.M. Smith, 1943 – Brown's coral snake (Quintana Roo to Honduras)
- Micrurus camilae Renjifo & Lundberg, 2003 (Colombia)
- Micrurus catamayensis Roze, 1989 – Catamayo coral snake (Catamayo Valley of Ecuador)
- Micrurus clarki K.P. Schmidt, 1936 – Clark's coral snake (southeastern Costa Rica to western Colombia)
- Micrurus corallinus (Merrem, 1820) - painted coral snake
- Micrurus decoratus (Jan, 1858) - Brazilian coral snake
- Micrurus diana Roze, 1983
- Micrurus diastema (A.M.C. Duméril, Bibron & A.H.A. Duméril, 1854) - variable coral snake
- Micrurus diastema aglaeope (Cope, 1859)
- Micrurus diastema alienus (F. Werner, 1903)
- Micrurus diastema affinis (Jan, 1858)
- Micrurus diastema apiatus (Jan, 1858)
- Micrurus diastema diastema (A.M.C. Duméril, Bibron & A.H.A. Duméril, 1854)
- Micrurus diastema macdougalli Roze, 1967
- Micrurus diastema sapperi (F. Werner, 1903)
- Micrurus dissoleucus (Cope, 1860) - pygmy coral snake
- Micrurus dumerilii (Jan, 1858)
- Micrurus elegans (Jan, 1858) - elegant coral snake
- Micrurus frontalis (A.M.C. Duméril, Bibron & A.H.A. Duméril, 1854) – southern coral snake (Brazil to northeastern Argentina)
- Micrurus frontifasciatus (F. Werner, 1927) - Bolivian coral snake
- Micrurus fulvius (Linnaeus, 1766) – eastern coral snake (U.S. coastal plains of North Carolina to Louisiana)
- Micrurus hemprichii (Jan, 1858) - Hemprich's coral snake
- Micrurus hippocrepis (W. Peters, 1862) - Mayan coral snake
- Micrurus ibiboboca (Merrem, 1820) - Caatinga coral snake
- Micrurus isozonus (Cope, 1860) - Venezuela coral snake
- Micrurus langsdorffi (Wagler, 1824) - Langsdorff's coral snake
- Micrurus laticollaris (W. Peters, 1870) - Balsan coral snake
- Micrurus latifasciatus K.P. Schmidt, 1933 - broad-ringed coral snake
- Micrurus lemniscatus (Linnaeus, 1758) - South American coral snake (most of low lying areas of South America)
- Micrurus margaritiferus Roze, 1967 - speckled coral snake
- Micrurus medemi Roze, 1967
- Micrurus mertensi K.P. Schmidt, 1936 - Merten's coral snake
- Micrurus mipartitus (A.M.C. Duméril, Bibron & A.H.A. Duméril, 1854) - redtail coral snake
- Micrurus multifasciatus (Jan, 1858) - many-banded coral snake
- Micrurus multiscutatus Rendahl & Vestergren, 1940 - Cauca coral snake
- Micrurus nebularis Roze, 1989 - cloud forest coral snake
- Micrurus nigrocinctus (Girard, 1854) – Central American coral snake (Yucatan and Chiapas to Colombia as well as western Caribbean islands)
- Micrurus nigrocinctus babaspul Roze, 1967
- Micrurus nigrocinctus coibensis K.P. Schmidt, 1936
- Micrurus nigrocinctus divaricatus (Hallowell, 1855)
- Micrurus nigrocinctus mosquitensis K.P. Schmidt, 1933
- Micrurus nigrocinctus nigrocinctus (Girard, 1854)
- Micrurus nigrocinctus ovandoensis K.P. Schmidt & H.M. Smith, 1943
- Micrurus nigrocinctus wagneri Mertens, 1941
- Micrurus nigrocinctus yatesi Dunn, 1942
- Micrurus nigrocinctus zunilensis K.P. Schmidt, 1932
- Micrurus pacaraimae Morato de Carvalho, 2002
- Micrurus pachecogili Campbell, 2000
- Micrurus paraensis da Cunha & Nascimento, 1973
- Micrurus peruvianus K.P. Schmidt, 1936 - Peruvian coral snake
- Micrurus petersi Roze, 1967 - Peters' coral snake
- Micrurus proximans H.M. Smith & Chrapliwy, 1958 - Nayarit coral snake
- Micrurus psyches (Daudin, 1803) - Carib coral snake
- Micrurus putumayensis Lancini, 1962 - Putumayo coral snake
- Micrurus pyrrhocryptus (Cope, 1862)
- Micrurus remotus Roze, 1987
- Micrurus renjifoi Lamar, 2003
- Micrurus ruatanus (Günther, 1895) - Roatán coral snake
- Micrurus sangilensis Nicéforo-María, 1942 - Santander coral snake
- Micrurus scutiventris (Cope, 1869)
- Micrurus silviae Di-Bernardo et al., 2007
- Micrurus spixii (Wagler, 1824) - Amazon coral snake
- Micrurus spurelli (Boulenger, 1914)
- Micrurus steindachneri (F. Werner, 1901) - Steindachner's coral snake
- Panamanian coral snake, Micrurus stewarti Barbour & Amaral, 1928
- Micrurus stuarti Roze, 1967 - Stuart's coral snake
- Aquatic coral snake, Micrurus surinamensis (Cuvier, 1817)
- Micrurus tamaulipensis Lavin-Murcio & Dixon, 2004 (Sierra Madre Oriental in Tamaulipas)
- Micrurus tener (Baird & Girard, 1853) – Texas coral snake (Texas and Louisiana south to Morelos and Guanajuato)
Mimicry[edit source | edit]
New World coral snakes serve as models for their Batesian mimics, False coral snakes, snake species whose venom is less toxic, as well as for many nonvenomous snake species that bear superficial resemblances to them. The role of coral snakes as models for Batesian mimics is supported by research showing that coral snake color patterns deter predators from attacking snake-shaped prey, and that in the absence of coral snakes, species hypothesized to mimic them are indeed attacked more frequently. Species that appear similar to coral snakes include:
- Cemophora coccinea
- Chionactis palarostris
- Erythrolamprus aesculapii
- Erythrolamprus bizona
- Erythrolamprus ocellatus, Tobago false coral
- Lampropeltis pyromelana
- Lampropeltis triangulum, milk snake, subspecies:
- Lampropeltis zonata
- Oxyrhopus petola
- Pliocercus elapoides, variegated false coral snake
- Rhinocheilus lecontei tessellatus
References[edit source | edit]
- "Coral Snakes, coral snake, pictures". Retrieved 24 November 2009.
- University of Georgia, Savannah River Ecology, Snakes of Georgia and South Carolina
- Western Connecticut State University
- Arizona-Sonora Desert Museum
- "Snake bites: MedlinePlus Medical Encyclopedia". Nlm.nih.gov. 2010-01-13. Retrieved 2010-11-16.
- "Antivenom Shortages – Cost of Antivenom Production Creates Shortages". Popular Mechanics. 2010-05-10. Retrieved 2010-11-16.
- "Our Products – Coralmyn". Bioclon.com.mx. Retrieved 2010-11-16.
- Brodie III, Edmund D. (1993). "Differential avoidance of coral snake banded patterns by free-ranging avian predators in Costa Rica". Evolution 47 (1): 227–235. doi:10.2307/2410131.
- Brodie III, Edmund D., Moore, Allen J. (1995). "Experimental studies of coral snake mimicry: do snakes mimic millipedes?". Animal Behavior 49 (2): 534–6. doi:10.1006/anbe.1995.0072.
- Pfennig, David W., Harcombe, William R., Pfennig, Karin S. (2001). "Frequncy-dependent Batesian mimicry". Nature 410 (6826): 323. doi:10.1038/35066628. PMID 11268195.
Further reading[edit source | edit]
- Boulenger, G.A. 1894. Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the Colubridæ (Opisthoglyphæ and Proteroglyphæ)... Trustees of the British Museum (Natural History). (Taylor and Francis, Printers.) London. xiv + 727 pp. + Plates I.- XXV. (Elaps, 28 species, pp. 411-433 + Plate XX.)
- Roze, J.A. 1996. Coral Snakes of the Americas: Biology, Identification, and Venoms. Krieger. Malabar, Florida. 340 pp. ISBN 978-0894648472.
- Tanaka G. D., Furtado Md. F. D., Portaro F. C. V., Sant'Anna O. A. & Tambourgi D. V. (2010). "Diversity of Micrurus Snake Species Related to Their Venom Toxic Effects and the Prospective of Antivenom Neutralization". PLoS Neglected Tropical Diseases 4(3): e622. doi:10.1371/journal.pntd.0000622