The coral treaders, Hermatobates Carpenter (Hemiptera : Hermatobatidae), of Australia and New Caledonia with notes on biology and ecology

Semiaquatic bugs (Heteroptera, infraorder Gerromorpha) are distributed worl dwide with approximately 1,600 described species. Most species live in vari ous types of freshwater habitats, but a little more than 10% have colonised the marine environment. The Australian fauna constitutes a significantly h igher percentage of marine species (about 25%) than in any other continent. Among these are the coral treaders, Hermatobates Carpenter, belonging to t he Hermatobatidae, one of very few insect families that only include marine species. In this paper the two species of Hermatobates previously known fr om Australia are redescribed and H. armatus, sp. nov. from the Chesterfield Islands in the Coral Sea is added. The distribution of species known from Australia and New Caledonia is mapped, and a revised key to the eight speci es currently recognised in the genus is presented. Finally, the available k nowledge about the biology and ecology of coral treaders is reviewed and di scussed.