Larvae 14–14.5 mm long; cephalic index 0.72–0.76, no more features which would permit differentiation of these larvae from Macropelopia nebulosa (Makarchenko & Petrova 1988).
Pupae 6.8 mm (male), 9.2 mm (female) long, yellow brown, with abdominal pigmentation patterns similar to M. nebulosa. Dorsal edge of thorax wrinkled. Thoracic horn (Figure 15 A), 592– 882 µm long, covered with small scales, plastron plate kidney-shape, 2.5 x wide a s long, index of plastron plate 0.14–0.22. On the tergites of II–VI setae D 1 arise from a large tubercle, on tergite VII the tubercles are small or reduced, setae D 3 straight. Segment VII with 6 taeniate L setae, VIII with 5. Anal lobe with fringe setae (84–88) (Figure 15 B).
Description. Tokunaga (1939) (as M. nebulosa), Fittkau (1962), Makarchenko & Petrova (1988).
Adult males. Description according to Makarchenko, Petrova (1988).
Ecology and distribution. Streams in Japan, Russia, Sakhalin, and Far East.