:''Common names: two-headed snakes.'' ''Micrelaps'' 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 ...

of rear-fanged mildly

venomous snake ''Venomous snakes'' are species of the suborder Serpentes that are capable of producing venom, which they use for killing prey, for defense, and to assist with digestion of their prey. The venom is typically delivered by injection using hollow ...

s. It is the only genus in the family Micrelapidae. The genus is native to

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

and the

Middle East The Middle East (term originally coined in English language) is a geopolitical region encompassing the Arabian Peninsula, the Levant, Turkey, Egypt, Iran, and Iraq. The term came into widespread usage by the United Kingdom and western Eur ...

, and there are four species that are recognized as being valid.

Taxonomy

Until very recently, this genus was classified 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 ...

Atractaspididae The Atractaspididae (atractaspidids) are a Family (biology), family of venomous snakes found in Africa and the Middle East, commonly called mole vipers, stiletto snakes, or burrowing asps. Currently, 12 genus, genera are recognized. Description ...

. However, a phylogenomic study published in 2023 on the ''Molecular Phylogenetics and Evolution'' journal has concluded that the genus should be re-classified into an autonomous family, apart from Atractaspididae, and thus created a new family called Micrelapidae, which constitutes a new Afro-Asian family of snakes.

Description

Species in the genus ''Micrelaps'' share the following characters: the

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

is very short, with two teeth, followed, after an interspace, by a very large grooved fang situated below the eye. The

mandibular In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

teeth are longest anteriorly. The head is small, and is not distinct from the neck. The eye is minute, and the pupil is round or vertically subelliptic. The nostril is pierced in a single

nasal scale In reptiles, the nasal scale refers to the scale that encloses the nostril. Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. 359 pp. . Somet ...

. There is no

loreal scale The lore (adj. loreal) is the region between the eyes and nostrils of birds, reptiles, and amphibians. Ornithology In ornithology, the lore is the region between the eye and bill on the side of a bird's head. This region is sometimes featherless ...

. There are no preocular scales, the prefrontal entering the eye. The body is cylindrical, and the tail is short. The

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 smooth, without pits, and are in 15 rows at midbody. The

ventral scales In snakes, the ventral scales or gastrosteges are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that cont ...

are rounded. The

subcaudal scales 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 ...

are in two rows.

Species

''*) Not including the nominate subspecies'' ^T)

Type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

Taxonomy

Description

Species

References

Further reading