Abstract
This taxonomic revision treats a radiation of Fijian ants described here as belonging to the Pheidole roosevelti-group. Many of the species belonging to the group exhibit remarkable modification to the shape of their propodeal spines, mesonotums and heads. Seven species, five of which are described as new, are recognized: P. bula sp. n., P. colaensis Mann 1921, P. furcata sp. n., P. pegasus sp. n., P. roosevelti Mann 1921, P. simplispinosa sp. n., and P. uncagena sp. n. Descriptions and diagnostic keys are provided for the minor workers, major workers and queens. All species are illustrated with digital images, and their distributions across the Fijian archipelago are illustrated with a map. The group is compared to congeners known from the Pacific Island region with special attention given to species of the Pheidole quadricuspis, P. quadrispinosa and P. cervicornis groups. The biogeography of the group is briefly discussed. Preliminary morphological study suggests the group is monophyletic and most closely related to species of the P. cervicornis- group Emery from New Guinea.References
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