Coral snake


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 16 species of Old World coral snake in three genera, and over 65 recognized species of New World coral snakes in three genera. Genetic studies have found that the most basal lineages are Asian, indicating that the group originated in the Old World.

North American coloration patterns

Experts now recognize that coloration patterns and common mnemonics which people use to identify the deadly coral snake are not 100% reliable. Some coral snakes do not have the typical banding colors or patterns. Examples of unreliable mnemonics commonly used for North American coral snakes:
Coral snakes in North America 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 usually, but not always, distinguishes between the non-venomous mimics and coral snakes native to North America: Micrurus fulvius, Micrurus tener, and Micruroides euryxanthus, found in the southeastern and southwestern United States. Coral snakes found in other parts of the world can have distinctly different patterns, have red bands touching black bands, have pink, blue, white, and black bands, or have no bands at all.
Most species of coral snake are small in size. North American species average around in length, but specimens of up to or slightly larger have been reported. Aquatic species have flattened tails acting as a fin, aiding in swimming.

Behavior

Coral snakes vary widely in their behavior, but most are very elusive, fossorial snakes which spend most 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.
Coral snakes feed mostly on smaller snakes, lizards, frogs, nestling birds, small rodents, etc.
Like all elapid snakes, coral snakes possess a pair of small hollow fangs to deliver their venom. The fangs are positioned at the front of the mouth. The fangs are fixed in position rather than retractable, and rather than being directly connected to the venom duct, they have a small groove through which the venom enters the base of the fangs. Because the fangs are relatively small and inefficient for venom delivery, rather than biting quickly and letting go, coral snakes tend to hold onto their prey and make chewing motions when biting. The venom takes time to reach full effect.
Coral snakes are not aggressive or prone to biting and account for less than one percent of the total number of snake bites each year in the United States. The life span of coral snakes in captivity is about seven years.

Distribution (U.S.)

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 plains 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, Arkansas, and sometimes in Oklahoma due to floods in the Red River, is separated from the eastern coral snake's habitat by the Mississippi River. The coral snake population is most dense in the southeastern United States, but coral snakes have been documented as far north as Kentucky.
The Arizona coral snake is classified as a separate species and genus and 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 5,800 feet ; often found in rocky areas.

Danger to humans

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 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.

Antivenom shortage

, the relative rarity of coral snake bites, combined with the high costs of producing and maintaining an antivenom supply, means that antivenom production in the United States has ceased. According to Pfizer, the owner of the company that used to make the antivenom Coralmyn, it would take between $5–$10 million for researching a new synthetic antivenom. The cost was too high in comparison to the small number of cases presented each year. The existing American coral snake antivenom stock technically expired in 2008, but the U.S. Food and Drug Administration has extended the expiration date every year through to at least 30th April 2017. Foreign pharmaceutical manufacturers have produced other coral snake antivenoms, but the costs of licensing them in the United States have stalled availability. Instituto Bioclon is developing a coral snake antivenom. In 2013, Pfizer was reportedly working on a new batch of antivenom but had not announced when it would become available., the Venom Immunochemistry, Pharmacology and Emergency Response institute of the University of Arizona College of Medicine was enrolling participants in a clinical trial of INA2013, a "novel antivenom," according to the Florida Poison Information Center.

Old World

Genus ''Calliophis''

in this genus are:
Nota bene: A binomial authority in parentheses indicates that the species was originally described in a different genus.

Genus ''Hemibungarus''

Species in this genus are:
Species in this genus are:

Genus ''[Leptomicrurus]''

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 snake
  • Lampropeltis elapsoides, scarlet kingsnake
  • Lampropeltis pyromelana
  • Lampropeltis triangulum, milk snake, including the following subspecies and others:
  • *Lampropeltis triangulum amaura
  • *Lampropeltis triangulum annulata
  • *Lampropeltis triangulum campbelli
  • *Lampropeltis triangulum gaigeae
  • *Lampropeltis triangulum gentilis
  • *Lampropeltis triangulum hondurensis
  • *Lampropeltis triangulum multistrata
  • *Lampropeltis triangulum syspila
  • Lampropeltis zonata
  • Lystrophis pulcher, tri-color hognose snake
  • Oxyrhopus petola
  • Oxyrhopus rhombifer, false coral snake
  • Pliocercus elapoides, variegated false coral snake
  • Rhinobothryum bovallii, coral mimic snake, false tree coral
  • Rhinocheilus lecontei tessellatus