Genus Microepicausta Hendel

Microepicausta Hendel, 1914a: 52–54 . Type species (original designation) M. gracilis Hendel.

Description and delimitation. See Hendel (1914a) and further notes by McAlpine (2001: 152). The genus should be identifiable from the key to platystomatid genera in McAlpine (2001: 121–130). The species superficially resemble those of Plagiostenopterina Hendel and Elassogaster Bigot, but the males have a single hollow terminal filament on the aedeagus, while apparently all related genera have two (rarely three) terminal filaments, each with apical gonopore.

Evenhuis (1989:493) listed six Australasian species of Microepicausta . His two included Australian species, M. gracilis Hendel and M. terraereginae (Malloch) are now considered to be synonyms, and M. evitta (Malloch) from the Bismarck Archipelago is now placed in the genus Par McAlpine, 2001 . The known Australian species, treated below, live on the northern and eastern Australian coasts as far south as Tasmania, with one record for coastal South Australia. Other species that I have seen range from West New Guinea to New Ireland and the Solomon Archipelago.

Habitat. In temperate eastern Australia, the two represented species, Microepicausta gracilis Hendel and M. wirthi sp. nov. are restricted to areas near the coast with a sandy substrate. Microepicausta wirthi is particularly restricted to the immediate vicinity of the shoreline on dunes and the landward borders of beaches. The flies have commonly been found on the native grass Spinifex sericeus, which is one of the most conspicuous plants in this habitat. Though the larvae of Microepicausta spp. are not yet known, I suspect that those of M. wirthi may be associated with the rhizomes or root systems of this plant.