Ants of Tonga

Abstract

This paper presents combined published, unpublished, and new ant records from 17 islands of Tonga representing all four island groups: Tongatapu (Tongatapu, 'Eua, 'Onevai, Pangaimotu), Ha'apai (Lifuka, Kao, Tofua, 'Uonukahahake, Nomuka, Nomuka-iki, Mango, Telekitonga), Vava'u (Vava'u, Nuapapu, Kapa), and the Niuas (Niuatoputapu, Niuafo'ou). These records increase the list of ants known from Tonga to 53 species. Ten species, including six undescribed species, are local endemics found only in Tonga or only in Tonga and Samoa: Adelomyrmex sp., Camponotus conicus, Camponotus nigrifrons, Hypoponera sp., Monomorium sp., Ochetellus sp., Pheidole sp., Pristomyrmex sp., Strumigenys zakharovi, and Vollenhovia samoensis. Another 21 species are broadly distributed Pacific natives: Anochetus graeffei, Camponotus chloroticus, Hypoponera confinis, Monomorium liliuokalanii, Monomorium talpa, Odontomachus simillimus, Oligomyrmex atomus, Pheidole oceanica, Pheidole sexspinosa, Pheidole umbonata, Ponera incerta, Ponera tenuis, Pyramica dubia, Rogeria stigmatica, Solenopsis papuana, Strumigenys godeffroyi, Tapinoma minutum, Technomyrmex albipes, Tetramorium insolens, Tetramorium pacificum, and Tetramorium tonganum. Finally, 22 species are not native to the Pacific region, but were brought to the region by human commerce: Anoplolepis gracilipes, Cardiocondyla emeryi, Cardiocondyla nuda, Hypoponera opaciceps, Hypoponera punetatissima, Monomorium floricola, Monomorium pharaonis, Monomorium sechellense, Paratrechina bourbonica, Paratrechina longicornis, Paratrechina vaga, Pheidole fervens, Pheidole megacephala, Plagiolepis alluaudi, Pyramica membranifera, Solenopsis geminata, Strumigenys emmae, Strumigenys rogeri, Tapinoma melanocephalum, Tetramorium bicarinatum, Tetramorium lanuginosum, and Tetramorium simillimum. The number of ant species now known from Tonga is much as would be expected based on the species-area relationship for the neighboring island groups of Fiji, Wallis and Futuna, and Samoa. Differences in ant species richness among these island groups is primarily due to a greater number of local endemics in the island groups with greater land area.