Enhydrina

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Megaclassis: Osteichthyes
Cladus: Sarcopterygii
Cladus: Rhipidistia
Cladus: Tetrapodomorpha
Cladus: Eotetrapodiformes
Cladus: Elpistostegalia
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Lepidosauromorpha
Superordo: Lepidosauria
Ordo: Squamata
Subordo: Serpentes
Infraordo: Caenophidia
Superfamilia: Elapoidea

Familia: Elapidae
Subfamilia: Hydrophiinae
Genus: Enhydrina
Species (2): E. schistosa – E. zweifeli
Name

Enhydrina Gray, 1849

Primary references

Gray 1849: Cat. Snakes Coll. Brit. Mus., 47.

Vernacular names
English: beaked sea snakes

Enhydrina, commonly known as the beaked sea snake, hook-nosed sea snake, common sea snake, is a genus of highly venomous sea snakes. Study of Enhydrina is important for the making of anti-venom. The only sea snake anti-venom available at this time is for snakes in Malaysia of the Species Enhydrina schistosa, often noted as E. schistosa.
Species

Enhydrina schistosa common throughout the tropical Indo-Pacific. This species is implicated in more than 50% of all bites caused by sea snakes, as well as the majority of envenomings and fatalities. Also called the Valakadyn sea snake.[1]
Enhydrina zweifeli snakes are found from New Guinea to Australia (Northern Territory and Queensland). As called Sepik or Zweifel's beaked sea snake. In the past they were thought to be Enhydrina schistosa, but after DNA testing are now provisionally identified as Enhydrina zweifeli. DNA test have shown they are not related to Enhydrina schistosa.[2][3]

Both species are found in shallow open sea, river mouths, estuaries, coastal lagoons, and mangrove forests. Normally in water from 3.7-22.2 meters deep. Usually over soft bottoms like mud and sand. Some are found in freshwater lakes in Cambodia and India. They have been found to travel up rivers. One was found 7 km upriver in Goa, India.
References

Footnotes

Valenta 2010, p. 153
Ukuwela, K.D.B. et al. (online 2012): Molecular evidence that the deadliest sea snake Enhydrina schistosa (Elapidae: Hydrophiinae) consists of two convergent species. Molecular Phylogenetics and Evolution, doi:10.1016/j.ympev.2012.09.031

fox News, Deadliest sea snake splits in two, By Douglas Main,, December 11, 2012

Bibliography

Heatwole, H. (1999). Sea Snakes. New South Wales: University of New South Wales Press.
Voris, Harold K. (1985). "Population size estimates for a marine snake (Enhydrina schistosa) in Malaysia." Copeia 1985 (4): 955–961
Valenta, Jiri (2010). Venomous Snakes: Envenoming, Therapy (2nd ed.). Hauppauge, NY: Nova Science Publishers. ISBN 978-1-60876-618-5.
Whitaker, Romulus Earl (1978). Common Indian Snakes: A Field Guide. Delhi: Macmillan. OCLC 4638773.