Six new species of Labiobaetis Novikova & Kluge (Ephemeroptera : Baetidae)from Madagascar with comments on the validity of the genus

The genus Labiobaetis recently has been reported from Madagascar by Lugo-Or tiz and McCafferty (1997). The two described species were only known from t he nymphal stage. Examination of material from more than 800 samples in Mad agascar allows descriptions of six new species: Labiobaetis longicercus, L. dambrensis, L nigrocercus, L. vulgaris, L. punctatus and L. gilliesi. They can be distinguished easily by the shape of the second segment of the labi al palp, the shape of the second segment of the maxillary palp, the setatio n of the labrum, the number of gills, the presence or absence of hindwings and coloration of the abdomen. At present, the imagoes of only five of the eight species are known. They can be identified by the presence or absence of hindwings, coloration of the wings, shape of the sclerotized process bet ween gonopods and shape of the third segment of the gonopods. As all the species assigned to Labiobaetis were recently reassigned to Pseu docloeon, the status and validity of the genera Labiobaetis and Pseudocloeo n are discussed.