Anderson's stream snake (''Opisthotropis andersonii''), also known commonly as Anderson's mountain keelback,Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Opisthotropis andersonii'', p. 8; ''O. maxwelli'', p. 171). 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 ...

snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...

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 native to

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

Etymology

The specific name, ''andersonii'', is in honor of Scottish herpetologist

John Anderson John Anderson may refer to: Business *John Anderson (Scottish businessman) (1747–1820), Scottish merchant and founder of Fermoy, Ireland * John Byers Anderson (1817–1897), American educator, military officer and railroad executive, mentor of ...

Geographic range

''O. andersonii'' is found in

Hong Kong Hong Kong ( (US) or (UK); , ), officially the Hong Kong Special Administrative Region of the People's Republic of China ( abbr. Hong Kong SAR or HKSAR), is a city and special administrative region of China on the eastern Pearl River Delt ...

and

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

. www.reptile-database.org.

Habitat

The preferred natural

habitat In ecology, the term habitat summarises the array of resources, physical and 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 ...

s of ''O. andersonii'' are

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' ...

and freshwater

wetlands A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...

, at altitudes of .

Description

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 ...

, ''O. andersonii'' is blackish olive. Ventrally it is whitish, except for the chin and

lower labials In reptiles, the sublabial scales, also called lower-labials or infralabials, are those scales that border the mouth opening along the lower jaw. They do not include the median scaleWright AH, Wright AA. 1957. ''Handbook of Snakes''. Comstock Publis ...

which are brown. The snout is short, broad, and depressed. There is a single prefrontal, and only one pair of

chin shield Chin shields or chinshields, genials scales on a snake are scales found on the underside of the snake's head towards the anterior and touching the lower labial scales. Chin shields to the front of the snake (towards the snout) are called anterior c ...

s. Boulenger GA (1893). ''Catalogue of the Snakes in the British Museum (Natural History). Volume I., Containing the Families Colubridæ ...'' London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I–XXVIII. (''Opisthotropis andersonii'', new combination, p. 284 + Plate XVIII, figures 3, 3a, 3b, 3c). 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 ...

, which are arranged in 17 rows throughout the entire length of the body, are smooth on the neck, feebly keeled at midbody, and strongly keeled on the tail. Adults of ''O. andersonii'' have a total length (including tail) of . The tail is 15–20 % of the total length.

Reproduction

''O. andersonii'' is

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...

Etymology

Geographic range

Habitat

Description

Reproduction

References

Further reading