The genus is divided into 2 subgenera, viz. Risiocnemis (typified by R. serrata [Hagen]) and Igneocnemis subg. nov. (typified by R. ignea [Brauer]). The subgenus Risiocnemis is revised. 14 of the known 15 spp., incl. 10 new spp., are classified into 4 species groups, viz. (I) appendiculata group ( appendiculala [Brauer], erythrura [Brauer], praeusta sp. n., confusa sp. n., kiautai sp. n., moroensis sp. n.); — (2) orator group (orator sp. n.); — (3) rolandmuelleri group (rolandmuelleri sp. n.); and — (4) serrata group (serrata [Hagen], asahinai Kitagawa, gracilis sp. n., varians sp. n., pulchra sp. n., laguna sp. n.). R. elegans Kitagawa is not placed into any group, since no material was available for examination. Of gracilis sp. n. only $ and from moroensis sp. n. only $ are known; from the other spp. n. both sexes are described. Females of R. appendiculata and R. erythrura are described for the first time. R. cornuta (Brauer), the lectotype of which is designated, is synonymized with R. serrata (Hagen). Separate keys to the males and females are given and a review of studies on the genus is presented.