''Cerberus rynchops'', also known as the New Guinea bockadam, South Asian bockadam, bockadam snake, or dog-faced water snake, is a mildly venomous

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 a

snake Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more j ...

in the family Homalopsidae. It is native to coastal waters of South and Southeast Asia. The species was re-delimited in 2012, allocating populations east and south of the west coast of Thailand to other species.

Ecology and behaviour

It is commonly found in

mangrove A mangrove is a shrub or tree that grows in coastal saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evolution in severa ...

s, mudflats, streams, ponds,

tidal pool A tide pool or rock pool is a shallow pool of seawater that forms on the rocky intertidal shore. Many of these pools exist as separate bodies of water only at low tide. Many tide pool habitats are home to especially adaptable animals that ...

s, on algae patches, and has even been found burrowing into the mud. It is rear-fanged and is mildly venomous. An aquatic and nocturnal snake, it feeds mainly on fish and is known to consume

eels Eels are ray-finned fish belonging to the order Anguilliformes (), which consists of eight suborders, 19 families, 111 genera, and about 800 species. Eels undergo considerable development from the early larval stage to the eventual adult stage ...

. In captivity, it is observed to move in a sidewinding direction on land. In the BBC series 'Life in Cold Blood' it was filmed adapting this sidewinding technique to jump across a mudflat in Singapore; up until then, no snakes were considered able to truly jump. It also has a

prehensile Prehensility is the quality of an appendage or organ that has adapted for grasping or holding. The word is derived from the Latin term ''prehendere'', meaning "to grasp". The ability to grasp is likely derived from a number of different orig ...

tail that would suggest it could climb mangrove trees. It is now known to give birth to live young, numbering from 8 to 30, either in water or on land. It is a quite docile, mild-tempered and a hardy snake; in recent years it has become a welcome addition to snake hobbyists in the Philippines. It also owes its popularity to its bright yellow to orange belly coloring, mostly of females. In the Philippines, particularly in the

Central Visayas Central Visayas ( ceb, Tunga-tungang Kabisay-an; tl, Gitnang Kabisayaan) is an administrative region in the Philippines, numerically designated as Region VII. It consists of four provinces: (Cebu, Bohol, Negros Oriental, and Siquijor) and thr ...

area, this snake is commonly known as the "tangkig". CerebrusRynchopsScales

Description

The visibility of upper jaw, giving it a dog-like appearance. Head long and distinct from neck. Eyes small and beady, with rounded pupils. Dorsum dark gray, with faint dark blotches and a dark line along the sides of the head, across the eyes. Center cream with two distinct rows of large, diffuse dark gray spots. Scales are distinctly keeled. Midbody scale rows 21–25. Ventrals 132–160. Subcaudals 49–72.

Distribution and habitat

This is a

saltwater Saline water (more commonly known as salt water) is water that contains a high concentration of dissolved salts (mainly sodium chloride). On the United States Geological Survey (USGS) salinity scale, saline water is saltier than brackish water, ...

-tolerant species found in India (including Andaman and Nicobar Islands), Bangladesh, Myanmar, Thailand, and northwestern Malaysia. The eastern limit of its distribution with ''

Cerberus schneiderii In Greek mythology, Cerberus (; grc-gre, Κέρβερος ''Kérberos'' ), often referred to as the hound of Hades, is a multi-headed dog that guards the gates of the Underworld to prevent the dead from leaving. He was the offspring of the mo ...

'' is uncertain.

References

External links

* https://web.archive.org/web/20080823125843/http://itgmv1.fzk.de/www/itg/uetz/herp/photos/Cerberus_rynchops.jpg * https://web.archive.org/web/20080823125753/http://itgmv1.fzk.de/www/itg/uetz/herp/photos/Cerberus_rynchops2.jpg * https://web.archive.org/web/20080823125637/http://itgmv1.fzk.de/www/itg/uetz/herp/photos/Cerberus_rynchops3.jpg * http://biodiversitycapiz.blogspot.co.za/2013/02/dog-faced-water-snake.html * https://web.archive.org/web/20070109093424/http://www.wildsingapore.per.sg/discovery/factsheet/snakedogfaced.htm * http://www.ecologyasia.com/verts/snakes/dog-faced_water-snake.htm {{Taxonbar, from=Q2442553 Colubrids Snakes of Southeast Asia Fauna of the Andaman and Nicobar Islands Reptiles of Bangladesh Reptiles of India Reptiles of Malaysia Reptiles of Myanmar Reptiles of Thailand Reptiles described in 1799 Taxa named by Johann Gottlob Theaenus Schneider Reptiles of Borneo

Ecology and behaviour

Description

Distribution and habitat

References

Further reading

External links