Abstract

A new paedogenetic midge (Diptera: Cecidomyiidae: Winnertziinae: Heteropezini) from O‘ahu Island, Hawai‘i, Neostenoptera hawaiiensis Plakidas, Nguyen, and Ferro, new species, is described and illus¬trated. A key to all species in the genus is provided. Specimens were emergent from deadwood gathered at Waimea Arboretum and Botanical Garden. Neostenoptera appalachiensis Plakidas and Ferro were collected from the same set of samples in Hawai‘i, and additional specimens are reported from Georgia and South Carolina, three new state records. The discovery of two paedogenetic midges in Hawai‘i poses a unique set of questions as to their possible mode of arrival on an island ecosystem. We briefly address the possibility that both species are simply “hitchhikers” that went undetected at ports of entry.

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