Rhabdophis

''Rhabdophis'' is a genus of snakes in the subfamily Natricinae of the family Colubridae. Species in the genus ''Rhabdophis'' are generally called keelback snakes, and are found primarily in Southeast Asia.

Toxicity

''Rhabdophis'' is often thought of as completely harmless, but there are several cases of severe envenomation and at least one recorded fatality from the Japanese species. The symptoms have been compared to those of highly venomous African colubrids such as the Boomslang. Similar reports exist for other species of the genus,Nelwan, Erni Juwita, et al. (2016)."Severe coagulopathy and transient hypertension following a ''Rhabdophis subminiatus'' bite: a case report". ''Revista da Sociedade Brasileira de Medicina Tropical'' nline 49 (4): 520–522. ccessed 16 November 2021 Available from: . ISSN 1678-9849. https://doi.org/10.1590/0037-8682-0314-2015. which also make reference to the highly hemorrhagic nature of the venom. There is a supposed antivenom in Japan, but not in other countries.

While the term "poisonous snake" is often incorrectly used for a wide variety of venomous snakes, some species of ''Rhabdophis'' are in fact poisonous but not venomous. Keelback snakes have salivary glands that secrete poison they ingest from eating poisonous toads. While both venom and poison are toxins, a venom requires direct delivery, for instance subcutaneously through a snake bite, but can be ingested without harm. A poison can also be absorbed indirectly, e.g., by touch or through the digestive system, or delivered by the fang of a poisonous snake.
''Rhabdophis'' ingest poisonous toads and the poison is absorbed into their blood stream, but the snake is immune to it. The toad poison now accumulates in their salivary glands which is secreted when they bite next time. Therefore, they use toad poison as their venom. Although this is harmful to small rodents, they cannot harm humans as the concentration of poison secreted is very low.

Species

These species are recognized as being valid:
*''Rhabdophis adleri''
*''Rhabdophis akraios'' – Singalang keelback
*''Rhabdophis angeli'' – Angel's keelback
*''Rhabdophis auriculatus'' – white-lined water snake
*''Rhabdophis barbouri'' – Barbour's water snake Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Rhabdophis barbouri'', p. 16; ''R. swinhonis'', p. 258).
*'' Rhabdophis bindi'' – Bindee keelback
*'' Rhabdophis callichroma'' – Bavi keelback
*'' Rhabdophis callistus'' – Boettger's keelback
*'' Rhabdophis ceylonensis'' – Sri Lanka blossom krait, Sri Lanka keelback
*'' Rhabdophis chiwen'' – Chiwen keelback
*'' Rhabdophis chrysargoides'' – Javanese keelback, Günther's keelback
*'' Rhabdophis chrysargos'' – specklebelly keelback
*'' Rhabdophis confusus''
*'' Rhabdophis conspicillatus'' – red-bellied keelback
*'' Rhabdophis flaviceps'' – orangeneck keelback, orange-lipped keelback, yellow-headed keelback
*'' Rhabdophis guangdongensis'' – Guangdong keelback
*'' Rhabdophis helleri'' – Heller’s red-necked keelback
*'' Rhabdophis himalayanus'' – orange-collared keelback
*'' Rhabdophis leonardi'' – Burmese keelback
*'' Rhabdophis lineatus'' – zigzag-lined water snake
*'' Rhabdophis murudensis'' – Muruden keelback, Gunung Murud keelback
*'' Rhabdophis nigrocinctus'' – black-striped keelback
*'' Rhabdophis nuchalis'' – Hubei keelback
*'' Rhabdophis pentasupralabialis''
*''Rhabdophis plumbicolor'' – green keelback, lead keelback
*'' Rhabdophis rhodomelas'' – blueneck keelback, blue-necked keelbac
*'' Rhabdophis siamensis''
*''Rhabdophis subminiatus'' – red-necked keelback
*'' Rhabdophis swinhonis'' – Swinhoe's grass snake
*''Rhabdophis tigrinus'' – tiger grooved-neck keelback, tiger keelback, Japanese grass snake, ''yamakagashi''

''Nota bene'': A binomial authority in parentheses indicates that the species was originally described in a genus other than ''Rhabdophis''.

References

External links

Animal Diversity Web list of species of ''Rhabdophis''

Further reading

* Fitzinger L (1843). ''Systema Reptilium, Fasciculus Primus, Amblyglossae''. Vienna: Braumüller & Seidel. 106 pp. + indices. (''Rhabdophis'', new genus, p. 27). (in Latin).

{{Taxonbar, from=Q1996924

Reptiles of Asia
Snake genera
Taxa named by Leopold Fitzinger