Chironomus (Chironomus) riparius Meigen, 1804

Yamamoto, Nao & Yamamoto, Masaru, 2018, Taxonomic information on some Japanese Chironomidae (Diptera) described by Dr. M. Sasa (†), Zootaxa 4514 (4), pp. 516-528 : 520

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.

Figures

FIGURES 10–18. Chironomus spp., male imagines. 10–14, Chironomus claggi Tokunaga, superior volsellae (10–11, specimens identified as C. claggi by Sasa & Suzuki, specimen No. 308:02; 11, specimen No. 307:04; 12–14, holotype of Chironomus simantobeceus Sasa, Suzuki et Sakai); 12, superior volsella; 13, tarsomere 1 of mid leg; 14, tarsomere 2 of mid leg. 15–17, Chironomus riparius Meigen (holotype of Chironomus ginzanbeceus Sasa et Suzuki), 15, abdominal tergites, 16, anal point, lateral aspect, 17, superior volsella, dorsal aspect. 18, Chironomus yoshimatsui Martin et Sublette (holotype of Chironomus echizensis Sasa, superior volsella, dorsal aspect).