Abstract
Two new species similar to Ophichthus megalops Asano, 1987 with dark-tipped anal fins, are described on the basis of one specimen of each species. Ophichthus semilunatus sp. nov. from northeastern Taiwan is characterized by having 176 total vertebrae, three rows of teeth on the maxilla, one + three supraorbital pores, two preopercular pores, a brownish anterior-nostril tube, and a blotch on the anterior margin of anus. Ophichthus brevidorsalis sp. nov. from New Caledonia is characterized by having two preopercular pores, one + three supraorbital pores, smaller eyes 2.7 in head, a short head 9.5% of total length, a long tail 59.8% of total length, a slightly short snout 19.4% of head, and 43 predorsal vertebrae. A redescription of O. megalops is provided based on the holotype and 18 specimens newly collected from Taiwan. Selected characters of all nine Ophichthus with a dark-tipped anal fin are provided. In addition, partial COI sequences of five species is provided.
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