Haliotrema species are described and/or reported from the gills of butterfly fishes (Chaetodontidae) from coral reefs of the Indo-West Pacific islands: Moorea (French Polynesia), Palau (Micronesia), Wallis (Wallis and Futuna), New Caledonia, Lizard Island and Heron Island (Great Barrier Reef, Australia). Haliotrema angelopterum sp. nov., a new species of Monogenoidea parasite from seven species of Chaetodon Linnaeus, 1758 (Chaetodontidae), is described. A new redescription and statute are given for Haliotrema aurigae (Yamaguti, 1968) comb. nov., a parasite from ten species of Chaetodon and one species of Heniochus Cuvier, 1816 (Chaetodontidae). New records of Haliotrema scyphovagina Yamaguti, 1968 are reported from two localities and from several host species belonging to the genera Chaetodon and Forcipiger Jordan and McGregor, 1898 (Chaetodontidae).