Fiji Ants

For a small cluster of islands in the remote reaches of the Pacific Ocean, the Fiji archipelago supports an enigmatically rich diversity of ants. A recent review of the literature revealed 138 described species and subspecies representing 32 genera. Several of these genera, such as Cerapachys, Gnamptogenys, Leptogenys, Proceratium, and Lordomyrma are more typical of continental ecosystems than isolated oceanic islands. Ninety-one of the described species (over 60%) are endemic to the archipelago, and a number of genera, such as Pheidole, Camponotus, and Strumigenys have undergone significant taxonomic radiation. There is one genus, Poecilomyrma, that is endemic to the archipelago and that appears to have diversified into three distinct species.

While the higher elevation rainforests of the larger islands serve as enclaves for the endemic species, much of the lowlands and smaller islands are inhabited by widespread pan-pacific species and exotic species. Although Anoplolepis gracilipes, Paratrechina vaga, Pheidole megacephala and Solenopsis geminata are currently impacting the native diversity, Wasmannia auropunctata is yet to establish populations on the archipelago.

A recently initiated survey of the Fijian ant fauna is providing large numbers of specimens from litter sifting, malaise trapping and hand collecting, and has recently added two additional genera, Acropyga and Discothyrea, to the ants of Fiji checklist. A series of faunistic revisions for the more diverse genera has begun in an attempt to describe some of the dozens of yet unnamed species collected during the survey. While the Camponotus-dominated arboreal fauna has been well-described, the ground fauna, and the ants inhabiting the leaf litter in particular, requires further sampling for a complete picture of the ants of the Fiji Islands.