''Micruroides'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

venomous 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 ...

coral snake Coral snakes are a large group of elapid snakes that can be divided into two distinct groups, the Old World coral snakes and New World coral snakes. There are 27 species of Old World coral snakes, in three genera ('' Calliophis'', '' Hemibungar ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Elapidae Elapidae (, commonly known as elapids , from , variant of "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 '' Emydocephalus ...

. The genus is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

, containing only the

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

''Micruroides euryxanthus''. ''Micruroides euryxanthus'', commonly known as the Sonoran coral snake, western coral snake or the Arizona coral snake, is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to northwestern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

and the

southwestern United States The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural list of regions of the United States, region of the United States that includes Arizona and New Mexico, along with adjacen ...

Description

Adults of ''M. euryxanthus'' are long. The color pattern consists of broad, alternating rings of red and black, separated by narrower rings of white or yellow. Markings become paler as they reach the belly. The head is black,Reptiles and Amphibians of Arizona. www.reptilesofaz.org/Snakes-Subpages/h-m-euryxanthus.html. the black extending to the posterior border of the parietals. The smooth

dorsal scales In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publis ...

are arranged in 15 rows at midbody. The ventrals number 214–241. The anal plate is divided. The

subcaudals In snakes, the subcaudal scales are the enlarged plates on the underside of the tail. Wright AH, Wright AA (1957). ''Handbook of Snakes of the United States and Canada''. Comstock Publishing Associates, a Division of Cornell University Press. (7t ...

number 21–34, and are divided (paired). Smith HM, Brodie ED Jr (1982). ''Reptiles of North America: A Guide to Field Identification''. New York: Golden Press. 240 pp. (paperback). ("Elapidsfamily Elapidae" and ''"Micruroides euryxanthus"'', pp. 196–197). ''Micruroides euryxanthus'' resembles ''

Micrurus fulvius ''Micrurus fulvius'', Common name, commonly known as the eastern coral snake,John L. Behler, Behler John L.; Frederic Wayne King, King, F. Wayne (1979). ''The Audubon Society Field Guide to North American Reptiles and Amphibians''. New York: Alf ...

''. However, the white or yellow rings are broader than in ''M. fulvius'', and there are fewer black rings on the tail, usually only 2. Also, the first ring on the body (the first ring behind the white or yellow ring on the back of the head) is red, whereas in ''Micrurus fulvius'' it is black.

Venom

The

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 ...

of ''M. euryxanthus'' is

neurotoxic Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specifical ...

and extremely potent, but no fatalities have been reported.

Habitat

''M. euryxanthus'' is found in arid and semiarid regions in numerous

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

s, both on plains and on lower mountain slopes, from sea level to . In Arizona it is abundant in rocky upland desert.

Behavior

The Sonoran coral snake usually stays underground and comes out at night, but can also appear during and after rains.

Defense

When startled, frightened, or threatened, ''M. euryxanthus'' will hide its head under its body and raise and tightly curl its tail. While in this posture, it will "fart": snakes do not have an anal cavity in the sense that humans and most mammals do, but rather a tract that allows for both disposal of waste and for laying of eggs in females. Instead, it will forcibly and noisily emit gas from its

cloaca A cloaca ( ), : cloacae ( or ), or vent, is the rear orifice that serves as the only opening for the digestive (rectum), reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles, birds, cartilagin ...

, a behavior known as "cloacal popping", and predictably this phenomenon has a very unpleasant smell.

Diet

The Arizona coral snake preys upon small snakes, predominantly '' Rena (snake)'', but also ''

Sonora Sonora (), officially Estado Libre y Soberano de Sonora (), is one of the 31 states which, along with Mexico City, comprise the Administrative divisions of Mexico, Federal Entities of Mexico. The state is divided into Municipalities of Sonora, 72 ...

'', and ''

Tantilla ''Tantilla'' is a large genus of harmless New World snakes in the family Colubridae. The genus includes 66 species, which are commonly known as centipede snakes, black-headed snakes, and flathead snakes. Wilson, Larry David (1982). Tanti ...

''.Hubbs B, O'Connor B (2012). ''A Guide to the Rattlesnakes and other Venomous Serpents of the United States''. Tempe, Arizona: Tricolor Books. 129 pp. (paperback). (''Micruroides euryxanthus euryxanthus'', pp. 86-87, 122). It will also eat small

lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...

s such as

skink Skinks are a type of lizard belonging to the family (biology), family Scincidae, a family in the Taxonomic rank, infraorder Scincomorpha. With more than 1,500 described species across 100 different taxonomic genera, the family Scincidae is one o ...

Reproduction

Like all other species of

New World The term "New World" is used to describe the majority of lands of Earth's Western Hemisphere, particularly the Americas, and sometimes Oceania."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: ...

coral snakes (

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

'' Leptomicrurus'' and ''

Micrurus ''Micrurus'' is a genus of venomous coral snakes of the family Elapidae. Geographic range Species in the genus ''Micrurus'' are endemic to the Americas. Species The following 82 species are recognized as being valid. *'' Micrurus albicinctus' ...

''), ''Micruroides euryxanthus'' is

oviparous Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (i.e., by laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings kno ...

. Adult females may lay up to 3

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the ...

s, and each hatchlings is in total length.

Geographic range

''Micruroides euryxanthus'' is found from central

Arizona Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...

and southwestern

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

Mazatlán Mazatlán () is a city in the Mexican list of states of Mexico, state of Sinaloa. The city serves as the municipal seat for the surrounding , known as the Mazatlán Municipality. It is located on the Pacific Ocean, Pacific coast across from th ...

in southern

Sinaloa Sinaloa (), officially the (), is one of the 31 states which, along with Mexico City, compose the Federal Entities of Mexico. It is divided into 18 municipalities, and its capital city is Culiacán Rosales. It is located in northwest Mexic ...

. Isolated populations are also found in the Chocolate Mountains, La Paz County, western Arizona and on

Tiburón Island Tiburón Island is the largest island in the Gulf of California and the largest island in Mexico, with an area of . It is uninhabited and it was made a nature reserve in 1963 by President Adolfo López Mateos. Etymology is Spanish language, Spa ...

in the

Gulf of California The Gulf of California (), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Vermejo''), is a marginal sea of the Pacific Ocean that separates the Baja California peninsula from ...

. Stebbins RC (2003). ''A Field Guide to Western Reptiles and Amphibians, Third Edition''. The Peterson Field Guide Series ®. Boston and New York: Houghton Mifflin. 533 pp. (paperback). (''Micruroides euryxanthus'', pp. 405–496 + Plate 44 + Map 181).

Subspecies

Three

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

are recognized, including the

nominotypical subspecies In biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology), but that can successfully interbreed. ...

."''Micruroides euryxanthus'' ". ITIS (Integrated Taxonomic Information System). www.itis.gov. *''Micruroides euryxanthus australis'' *''Micruroides euryxanthus euryxanthus'' *''Micruroides euryxanthus neglectus'' ''

Nota bene ( ; plural: ) is the Latin language, Latin phrase meaning ''note well''. In manuscripts, ''nota bene'' is abbreviated in upper-case as NB and N.B., and in lower-case as n.b. and nb; the editorial usages of ''nota bene'' and ''notate bene'' fi ...

'': A trinomial authority in parentheses indicates that the subspecies was originally described in a different genus than the one within which it is currently classified.