Hydrophis atriceps Günther, 1864

Rasmussen, Arne Redsted, Sanders, Kate Laura, Guinea, Michael L. & Amey, Andrew P., 2014, Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae) - a review with an updated identification key, Zootaxa 3869 (4), pp. 351-371 : 353

Hydrophis atriceps Günther, 1864 .

Hydrophis fasciatus atriceps was mentioned by Smith (1926) as occurring in Australian waters based on one specimen from the Australian Museum (AMR6715) and two specimens close to Australian waters ( Aru Island and Kaiser Wilhelmsland, New Guinea). Cogger (1975) mentioned the same specimen as Smith, but had doubts about the locality and suggested the specimen was collected in Asian waters. Cogger also mentioned another juvenile specimen collected from Darwin (AMR14022) that he regarded as a H. fasciatus fasciatus ( Schneider, 1799) . We have examined the same specimen and agree with Cogger’s (1975) identification using Smith’s (1926) characters to separate the two subspecies. The identification and distribution of the two taxa remains based on Smith´s monograph from 1926, where he separated them at a subspecies level and mentioned the typical form occurs to west of the Malay Peninsula and the other form is found east of it throughout the Malay Archipelago to Australia. Smith also indicated the dividing line is in the region of Singapore, despite including a specimen from China in the western subspecies and two specimens from India and Rangoon in the eastern form. The specimen from China included by Smith in the western form (H. f. fasciatus ) is the type of Hydrophis lindsayi (Gray, 1831) , which antedates the name H. f. atriceps by 22 years, indicating that if the taxa are separated into two geographically distinct forms and this specimen was incorrectly assigned by Smith (1926) to H. f. fasciatus , the right name for the eastern population would be H. fasciatus lindsayi and not H. fasciatus atriceps . Later, Cogger et al. (1983) raised the two taxa to species level, referring the Australian specimens to H. atriceps . Ward (1996) assigned five specimens to H. atriceps from the northern Australian continental shelf. All the specimens were collected by prawn trawling ships ( Ward, 1996).

It seems likely the characters used by Smith (1926) and all subsequent taxonomists to separate H. fasciatus and H. atriceps -scale rows around the neck and body together with ventrals -are not useful to assign correctly all specimens to species level in this complex. Whether the name for an Australian population of the H. fasciatus complex proves to be atriceps , fasciatus or lindsayi , we regard the species to be in Australian waters based on at least one specimen from the region of Darwin (AMR14022) and the specimens mentioned by Ward (1996). We suggest using the name H. atriceps for the Australian population of this species until further taxonomic clarification.