A REVISION OF THE SHORE-FLY GENERA HOSTIS-CRESSON AND PARATISSA-COQUILLETT (DIPTERA, EPHYDRIDAE)

The shore-fly genera Hostis Cresson and Paratissa Coquillett are revised. These genera, now placed in the tribe Psilopini, are sister groups to each other. Hostis, which is monotypic, occurs on maritime beaches of the Pacific and Indian oceans. Acanthonotiphila scotti Seguy is a junior synonym of Hostis guamensis Cresson. Paratissa, comprising four species, includes P. neotropica, which is newly described (type locality: Belize. Stann Creek District: Carrie Bow Cay); also, P. coriacea (Lamb), P. semilutea (Loew), and P. pollinosa (Williston). The latter three species had been considered to be conspecific but are here shown to be valid species.