Ants (Hymenoptera: Formicidae) of Samoa

Abstract

The ants of Samoa have been well studied compared with those of other Pacific island groups. Using Wilson and Taylor's (1967) specimen records and taxonomic analyses and Wilson and Hunt's (1967) list of 61 ant species with reliable records from Samoa as a starting point, we added published, unpublished, and new records of ants collected in Samoa and updated taxonomy. We increased the list of ants from Samoa to 68 species. Of these 68 ant species, 12 species are known only from Samoa or from Samoa and one neighboring island group, 30 species appear to be broader-ranged Pacific natives, and 26 appear to be exotic to the Pacific region. The seven-species increase in the Samoan ant list resulted from the split of Pacific Tetramorium guineense into the exotic T. bicarinatum and the native T. insolens, new records of four exotic species (Cardiocondyla obscurior, Hypoponera opaciceps, Solenopsis geminata, and Tetramorium lanuginosum), and new records of two species of uncertain status (Tetramorium cf. grassii, tentatively considered a native Pacific species, and Monomorium sp., tentatively considered an endemic Samoan form).