The Recently Extinct Plants and Animals Database

Hydrophis vorisi Kharin, 1984

Estuarine sea snake, Plain-banded seasnake



Taxonomy & Nomenclature

According to the dichotomous key provided by (Rasmussen, 2001), the Estuarine Sea Snake (Hydrophis vorisi) exhibits the following unique combination of characters:

* "Localit[y] different from Lake Taal in Luzon, Philippines" (paraphrasing)
* "Ventrals normally entire and distinct throughout"
* "At least 22 scale rows around neck"
* "Less than 14 maxillary teeth behind the poison-fangs"
* "At least 5 maxillary teeth behind the poison-fangs"
* "At least 37 scale rows around neck"
* "Dorsal part of body with parallel bands anteriorly and normally the interspaces 2 or less scales wide, and/or 42 bands or more on body and tail"
* "Less than 275 ventrals; more than 29 scale rows around neck"
* "Bands on body 38 or more, and/or 10 or more maxillary teeth behind the poison fangs"
* "Less than 280 ventrals; more than 36 scale rows around body"
* "Scale rows around neck 30 or more, and/or body without 2 or 3 series of spots or
dark-edged markings"
* "More than 49 scale rows around body; less than 8 maxillary teeth behind the poison fangs"
* "Number of ventrals less than 280 or more than 330; no rows of regular black pentagonal markings on side of body"
* "At least 9 maxillary teeth behind the poison-fangs"
* "More than 27 scale rows around neck; more than 1 postocular"
* "Body with bands"
* "Bands not parallel behind head, and/or tail with less than 6 bands"
* "Bands not strongly dilated dorsally, and/or bands on tail not weak"
* "More than 400 ventrals"
* "Scale rows around body 47 or less, and/or head with lighter markings"
* "More than 340 ventrals; more than 36 scale rows around body"
* "No small spots between bands on body"
* "Ventrals 325 or more, and/or 42 or more bands on body"
* "Head small, not more than 8 mm wide; neck long and narrow, posterior part of body more than 2 times the neck"
* "Less than 25 scale rows around neck; ventrals 320 to 360; at least 70 bands on body
and tail"


Conservation Status

Last record: c.1972?

IUCN RedList status: Data Deficient



Fly River, Papua New Guinea (southern)


Biology & Ecology




Holotype: AMNH 58869

Only known from two specimens (Rasmussen & Guinea, 2010; Rasmussen et al. 2014:355), including MCZ 141979.






Original scientific description:

Kharin, V. E. (1984). A review of sea snakes of the group Hydrophis sensu lato (Serpentes, Hydrophiidae). S. The genus Leioselasma. Zoologicheskii Zhurnal, LXIII:1535-1546.


Other references:

Clayton, M., Wombey, J.C., Mason, I.J., Chesser, R.T. & Wells, A. (2006). CSIRO List of Australian Vertebrates: A Reference with Conservation Status. Melbourne : CSIRO Publishing iv 162 pp.

O'Shea, M. (1996). A Guide to the Snakes of Papua New Guinea. Independent Publishing, Independent Group Ltd., Port Moresby, PNG.

Rasmussen, Arne Redsted. (2001). Sea snakes. In: Carpenter, K.E. and Niem, V.H. (Eds.) Living Marine resources of the Western central Pacific. Food and Agriculture Organization, Rome, pp. 3987-4000. [available from: www[dot]fisheries[dot]go[dot]th/if-suratthani/web2/images/download/v666.pdf]

Rasmussen, A. & Guinea, M. (2010). Hydrophis vorisi. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. ( Downloaded on 28 April 2012.

Rasmussen, Arne Redsted, Sanders, Kate Laura, Guinea, Michael L. and Amey, Andrew P. (2014). Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)—a review with an updated identification key. Zootaxa 3869(4): 351-371.


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