With ages of many Pacific islands well known, and molecular and morphological reconstructed phylogenies available, including cytological information, a biogeography of the some 50 species in the simuliid subgenus Inseliellum can be attempted. Emphasis will be placed on morphology of the larvae. Paleogeology suggest that entry into the Pacific took place 20 Ma. A basal clade that possesses a displaced nucleolar organiser is the most widely spread, occurring in Micronesia, Tonga, Austral and Marquesas Islands. Within Society Islands the basal species, which are habitat generalists, are on almost all islands that possess running water. There has been a major species radiation on Tahiti and the reconstructed phylogeny based on morphology indicates that there has been back dispersal to western older islands. However, molecular evidence indicates that age of some species is older than that of Tahiti, indicative of origins on older western Society Islands. Similar evidence indicate very recent evolutionary events on Tahiti within the last 17-2 thousand years. Dispersal to older western islands of derived species, with specialized habitat requirements, is not possible because erosion has removed suitable habitats.
Species 1: Diptera Simuliidae inseliellum (black flies)
Keywords: Pacific Islands black flies
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA