THE SPECIES OF THE NEMOURA-OVOCERCIA GROUP (PLECOPTERA, NEMOURIDAE)

The Nemoura ovocercia group is revised, and diagnostic characters are provided for adults. Of the species originally included in the species -group, N. tau Zwick and N. akagii Kawai are removed to a new group, t he tau group, two additional species, N. cochleocercia Wu and N. lahki puri Aubert, are uncertain in the position of species-group, and they are not considered in this paper. Sixteen species are included in the ovocercia-group at present, nine of them are new to science: N. anguic ulus, N. dentata, N. dentigera, N. formosana, N. longilobata, N. quadr ituberata, N. saetifera, N. trivittata and N. zoahensis. Seven additio nal spe species were already known: N. babai Kawai, N. geei Wu (= N. b revicercia Zhiltzova, syn. n.), N. kuwayamai Kawai, N. longicercia Oka moto, N. ovocercia Kawai, N. redimiculum Kawai and N. sachalinensis Ma tsumura. They are presently known only from East Asia including the Ru ssian Far East, China, Taiwan and Japan.