''Boiga andamanensis'', known
commonly as the Andaman cat snake, is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
rear-fanged snake in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Colubridae
Colubridae (, commonly known as colubrids , from la, coluber, 'snake') is a family of snakes. With 249 genera, it is the largest snake family. The earliest species of the family date back to the Oligocene epoch. Colubrid snakes are found on ever ...
. The species is
endemic
Endemism is the state of a species being found 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 found elsew ...
to the
Andaman Islands
The Andaman Islands () are an archipelago in the northeastern Indian Ocean about southwest off the coasts of Myanmar's Ayeyarwady Region. Together with the Nicobar Islands to their south, the Andamans serve as a maritime boundary between th ...
.
Description
The body of ''B. andamanensis'' is long, thin, and laterally compressed, with 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 ...
. The head is distinctly broader than the neck. The eye is large, and has a vertical pupil. The tail is long.
Dorsally
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...
, the Andaman cat snake is pale reddish or greyish brown, uniform, or with a series of dark brown vertebral spots or thin cross-lines. There is dark colour usually on the scale edges. The markings are most distinct on the forebody. The top of the head has faint, dark brown or black lines. The upper lip scales are white, the last few with thin black rear edges. There is an indistinct black line from behind the eye to the angle of the mouth. The underside of the body is white or yellowish, usually with a series of black spots on each side. Juveniles and sub-adults are similarly patterned, and usually dark orange above, paler below. Most of the scales on the top of the head vary in shape and size, and are distinctly larger than the dorsal scales. The average adult total length (including tail) is approximately ,
but it may grow to a total length of .
Scalation
Dorsal scales in 21:21:15 oblique rows, smooth; vertebral scales distinctly enlarged.
Ventrals
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 ...
255–269, strongly angulate laterally;
anal
Anal may refer to:
Related to the anus
*Related to the anus of animals:
** Anal fin, in fish anatomy
** Anal vein, in insect anatomy
** Anal scale, in reptile anatomy
*Related to the human anus:
** Anal sex, a type of sexual activity involvin ...
entire;
subcaudals
In snakes, the subcaudal scales are the enlarged plates on the underside of the tail.Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . These scales may be either single or divided (pair ...
118–133, paired.
Loreal 1;
preocular
In scaled reptiles, the ocular scales are those forming the margin of the eye.Wright AH, Wright AA. 1957. ''Handbook of Snakes''. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . The name originates from the term ''oculus'' which ...
1, reaches upper surface of head, often touches frontal; postoculars 2, rarely 3;
temporals 3+3 or 3+4;
supralabials
In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scaleWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates ( ...
8 (3rd to 5th touching eye).
Geographic range
''B. andamanensis'' is endemic to the Andaman islands of
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
.
[
]
Habitat
The Andaman cat snake is a forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
species and is also frequently found in thatched roofs of houses.[
]
Behaviour and ecology
''B. andamanensis'' is nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
and arboreal
Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...
. It is occasionally seen on the ground searching for prey. It generally has a mild disposition but has been observed to strike when approached. If provoked it will raise its forebody, coil into loops, often vibrating its tail, and bite readily. It is a rear-fanged snake and has a mild venom which can paralyze small prey.[ It preys mainly on geckos, other small lizards (especially lizards of the ]genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Calotes
''Calotes'' is a genus of lizards in the draconine clade of the family Agamidae. The genus contains 29 species. Some species are known as forest lizards, others as " bloodsuckers" due to their red heads, and yet others (namely '' C. versicolo ...
''), and rodents, but will occasionally eat tree frogs and bats.[
]
References
Further reading
* Das I (2002). ''A Photographic Guide to Snakes and other Reptiles of India''. Sanibel Island, Florida: Ralph Curtis Books. 144 pp. . (''Boiga andamanensis'', p. 21).
* Wall F (1909). "Remarks on some forms of ''Dipsadomorphus'' ". ''Records of the Indian Museum'' 3: 151–155. (''Dipsadomorphus andamanensis'', new species, pp. 153–154).
{{Taxonbar, from=Q2908837
andamanensis
Endemic fauna of the Andaman Islands
Reptiles of India
Taxa named by Frank Wall
Reptiles described in 1909