Identification keys, descriptions and illustrations are provided for the genera and species of Anadyomene (3 spp.), Microdictyon (3 spp.), Boergesenia (1 sp.), Boodlea (2 spp.), Struvea (1 sp.), Phyllodictyon (2 spp), Dictyosphaeria (3 spp.), Valonia (4 spp.) and Ventricaria (I sp.) based on the specimens collected in Papua New Guinea and Indonesia from 1980 to 1994. Four new records for the region were found : Microdictyon okamurae (collected in the Banda and Flores Sea, Indonesia), Microdictyon palmeri and Phyllodictyon gardineri (collected along the N coast of Papua New Guinea), and Dictyosphaeria ocellata (collected along the S coast of Papua New Guinea). test