Fiji Ants

For a small cluster of islands in the remote reaches of the Pacific Ocean, the Fiji archipelago supports an enigmatically rich community of ants that includes 142 described species in 41 genera. Several of these genera, such as Cerapachys, Gnamptogenys, Leptogenys and Proceratium, are more typically found in continental biotas than on isolated oceanic islands. Ninety-five of the described species (over 60%) are endemic to the archipelago, and a number of genera, such as Pheidole, Camponotus, Hypoponera, Lordomyrma and Strumigenys, have undergone significant taxonomic radiation. One genus, Poecilomyrma, is endemic to the archipelago and appears to have diversified into at least three species.

While the higher elevation rainforests of the larger islands serve as enclaves for the endemic ants, much of the lowlands and smaller islands are dominated by widespread pan-pacific species and exotic species. Although Anoplolepis gracilipes, Paratrechina vaga, Pheidole megacephala and Solenopsis geminata, among others, are excluding native ants from marginal habitats, neither Wasmannia auropunctata nor Solenopsis invicta have established populations on the archipelago.

A new intensive survey of the Fijian ant fauna is underway and producing large numbers of specimens from litter sifting, malaise trapping and hand collecting. The survey has added several more genera, including Acropyga, Discothyrea, and Metapone, and dozens of undescribed species to the archipelago’s checklist (Ward & Wetterer, 2006). A series of faunistic revisions for the more diverse genera are now attempting to describe some of the dozens of as-yet-unnamed species collected during the survey (Sarnat, 2006). While the Camponotus-dominated arboreal fauna has been well-described, the ground fauna, and the leaf litter ants in particular, require further sampling for a complete picture of the ants of Fiji.

Eli M. Sarnat and Evan P. Economo
Fiji Ant Curators

See also Ants of Fiji.