Species of Taeniacanthus Sumpf, 1871 (Crustacea: Copepoda: Taeniacanthidae) parasitic on boxfishes (Tetraodontiformes: Aracanidae and Ostraciidae) from the Indo-West Pacific region, with descriptions of two new species.

Two new copepod species of the genus Taeniacanthus Sumpf, 1871 (Cyclopoida: Taeniacanthidae) are described from boxfishes (Aracanidae and Ostraciidae) caught in the Indo-West Pacific region: T. larsonae n. sp. from Ostracion nasus Bloch in the Arafura Sea and off Australia and Tetrosomus concatenatus (Bloch) off Japan; and T. thackerae n. sp. from O. immaculatus Temminck & Schlegel off Palau, O. rhinorhynchos Bleeker off Australia, Lactoria cornuta (Linnaeus) and Ostracion sp. off Japan, and Kentrocapros aculeatus (Houttuyn) in the East China Sea. T. larsonae n. sp. differs from its congeners by having several rows of spinules on the large pectinate process of the antenna and by differences in the shape of the sclerotised plates on the rostral area and structure of the maxilliped. T. thackerae n. sp. can be distinguished from its congeners by differences in the shape of the sclerotised plates on the rostral area, the structure of the maxilliped and ornamentation pattern of legs 1-4. Supplemental information for the female of Taeniacanthus ostracionis (Richiardi, 1870) and T. moa (Lewis, 1967), as well as the first description of the male of T. moa, are also provided based on new material collected from ostraciid hosts caught in the Arafura Sea and off Australia, Indonesia and Japan. The four taeniacanthid species reported from boxfishes exhibit variable levels of host-specificity and have broad geographical ranges within the Indo-West Pacific region.