The genus Haliophis presently consists of two species, H. guttatus (Forsskål, 1755), and a new species from Bali, Indonesia. Descriptions, diagnoses, and a key are provided for these taxa. A step cline occurs in H. guttatus, which ranges from 15° S to 30° N in the western Indian Ocean and Red Sea. Populations from 27 to 30°N differ most from those in the southern Red Sea and Gulf of Aden, but less so from those south of the equator. The step occurs between 20 and 27° N, an area from which no specimens were located, and is congruent with the distributions of at least four other taxa of fishes as well as with several populational differences in other species. This indicates that these distributional patterns may form part of a generalized track, rather than being the result of ecophenotypic effects. In the Red Sea – northern Indian Ocean region, the most common distribution of endemic fishes includes both the Red Sea and the Gulf of Aden. This pattern was not apparent in populations of H. guttatus.
Torpedo adenensis, a New Species of Electric Ray from the Gulf of Aden, with Comments on Nominal Species of Torpedo from the Western Indian Ocean, Arabian Sea, and Adjacent Areas (Chondrichthyes: Torpediniformes: Torpedinidae)
