Coral snake (Micrurus sp.)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Leptomicrurus
Calliophis
Micrurus
Micruroides
Species
The Distribution of the US Coral Snakes, some species range father south
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).
Contents
1 North American Coloration Patterns
2 Behavior
3 Distribution
4 vEnOm
1 North American Coloration Patterns
2 Behavior
3 Distribution
4 vEnOm
Coral snakes are most notable for their red, yellow/white, and black colored banding. (Several nonvenomous species have similar coloration, however, including the Scarlet Kingsnake, the Milk Snake, and the Chionactis occipitalis annulata.) In some regions, the order of the bands distinguishes between the non-venomous mimics and the venomous coral snakes, inspiring some folk rhymes — "Red on yellow, kill a fellow; red on black, friend of Jack" (for similar looking Milk Snakes). However, this only reliably applies to coral snakes native to North America: Micrurus fulvius (Eastern or common), Micrurus tener (Texas), and Micruroides euryxanthus (Arizona), found in the southern and eastern 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, to act as a fin, aiding in swimming.
Behavior
Coral snake showing typically reclusive behavior of hiding under rotting wood. This one was over 30 inches long, but less than an inch across.
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, only coming to the surface during 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 use a pair of small fangs fixed in the front of their top jaw to deliver their venom. They feed on smaller snakes, lizards, frogs, and nestling birds and rodents etc. The venom takes time to fully take 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 and let go immediately. Coral snakes are not aggressive or prone to biting however, and account for less than one percent of the number of snake bites each year in the United States. Most coral snake bites in the United States are legitimate occurring because of accidental contact with the snake while engaged in an outdoor activity such as gardening.
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, only coming to the surface during 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 use a pair of small fangs fixed in the front of their top jaw to deliver their venom. They feed on smaller snakes, lizards, frogs, and nestling birds and rodents etc. The venom takes time to fully take 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 and let go immediately. Coral snakes are not aggressive or prone to biting however, and account for less than one percent of the number of snake bites each year in the United States. Most coral snake bites in the United States are legitimate occurring because of accidental contact with the snake while engaged in an outdoor activity such as gardening.
Distribution
Eastern Coral Snake, Micrurus fulvius
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 sandhills 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 map here shows the denser population in the southeast United States but coral snakes have been spotted as far north as Kentucky.
The Arizona coral snake, clearly a separate species, 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.
Eastern Coral Snake, Micrurus fulvius
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 sandhills 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 map here shows the denser population in the southeast United States but coral snakes have been spotted as far north as Kentucky.
The Arizona coral snake, clearly a separate species, 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.
vEnOm
New World coral snakes possess the second most potent venom of any North American snake, behind some rattlesnake species. However, few bites are recorded due to their reclusive nature and the fact they generally inhabit sparsely populated areas. 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 breathing difficulties and ptosis can occur within hours.
The bite of a coral snake may soon become increasingly more dangerous, ironically because of the relatively few bites each year. Production of coral snake antivenom in the United States has ceased because it is not profitable. The current antivenom stock is scheduled to expire in 2010, after two consecutive expiration date extensions approved by the FDA. Foreign pharmaceutical manufacturers have produced coral snake antivenoms such as Coralmyn, but the costs associated with licensing them in the United States have stalled availability.
New World coral snakes possess the second most potent venom of any North American snake, behind some rattlesnake species. However, few bites are recorded due to their reclusive nature and the fact they generally inhabit sparsely populated areas. 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 breathing difficulties and ptosis can occur within hours.
The bite of a coral snake may soon become increasingly more dangerous, ironically because of the relatively few bites each year. Production of coral snake antivenom in the United States has ceased because it is not profitable. The current antivenom stock is scheduled to expire in 2010, after two consecutive expiration date extensions approved by the FDA. Foreign pharmaceutical manufacturers have produced coral snake antivenoms such as Coralmyn, but the costs associated with licensing them in the United States have stalled availability.
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