Taxonomic information on some Japanese Chironomidae (Diptera) described by Dr. M. Sasa (†) Author Yamamoto, Nao Author Yamamoto, Masaru text Zootaxa 2018 2018-11-09 4514 4 516 528 journal article 27979 10.11646/zootaxa.4514.4.5 b6786141-b3af-4df8-838b-6ecea1fd2810 1175-5326 2609358 CA29ED01-E74F-4DBB-AB6D-5055A03949BF Chironomus ( Chironomus ) riparius Meigen, 1804 ( Figs. 15–17 ) Chironomus riparius Meigen, 1804: 13 . Chironomus riparius : Sasa & Kamimura, 1987a : 15 ; Sasa, 1989 : 16 . 76; Sasa & Suzuki, 2000b : 178 . Chironomus ginzanbeceus Sasa et Suzuki, 2001a : 10 . syn. n. Specimen examined: Japan : Hokkaido , Ginzan , holotype ♂ of Chironomus ginzanbeceus , 2. ix. 2000 , H. Suzuki [specimen No. 403:005 (NSMT-I-Dip 5 381)] . The morphological features of Chironomus ginzanabeus are consistent with those of C . riparius redescribed by Sasa & Kamimura (1987a) . C. riparius sensu Sasa & Kamimura is not clearly separated from C . trinigrivittatus Tokunaga, 1940 (described from Sakhalin), in the hypopygial structure, although the colour patter and size of the body are different. The former has abdominal tergites 2–4 each with a broad brown band, on the other hand the latter has nearly uniformly darkened abdomen. In Japan , we recognized that the former species is distributed in level ground of northern Honshu and Hokkaido , and the latter species is collected from the bock of mountainous area of midland of Honshu. At this time, we cannot determine whether the gaps of features between these species mentioned above are caused by interspecific difference or intraspecific variations. For giving the precise answer, we need to know the comprehensive information about the immature stages and information based on a molecular analysis.