Cardinalfishes of the genus Nectamia (Apogonidae, Perciformes) from the Indo-Pacific region with descriptions of four new species

The status of Nectamia is re-examined. General morphology including gill arches, cephalic lateralis pores, dorsal-fin elements, scale characteristics and results from recent contributions support recognition as a genus rather than a subgenus. Nine species are removed from Ostorhinchus and placed in Nectamia. Neotypes are established for Apogon fuscus, the type species of Nectamia and for N. bandanensis. Four undescribed species, Nectamia ignitops, N. luxuria, N. similis, and N. viria, having been confused with N. bandanensis, N. fusca and N. savayensis. Two species, Nectamia annularis and N. zebrinus are endemic to the Red Sea. Meristics or morphometrics, absent good color patterns will not conclusively identify each species. A key to the species is provided. Four species are polymorphic with respect to number of gill rakers. Gill-raker variation can be associated with geographic patterns: Red Sea, East Africa plus Mascarene Plateau, China Sea, Indonesia plus Philippines, Palau to Wake I., and Southeast Indonesia-Coral Sea to Mangareva. Color patterns are used in an analysis of phylogeny of the species. Five names are treated as synonyms: Apogon erdmani, a synonym of Nectamia annularis and Apogon guamensis, Apogon nubilus, Apogon ocellatus, and Apogon spongicolus, as synonyms of N. fusca.