Anterior-margin setae of segment 9 small; anterior-angle and medio - 

 anal setae situated close together, strong, relatively long, situated posterior 

 549 to small, brownish sclerite on sides of segment; between them a short, thin, 

 brown, intermediate setae and a hairlike lateral seta. Numerous long, 

 strong, golden brown, secondary setae at sides, which are thicker and 

 darker than on segment 8. Sides ventrally with oblong (not triangular) 

 yellowish plates; anterior part of these plates with dense, short setae; setae 

 have a broad, reddish brown base and a long, light end; posterior part of 

 plates with dense, reddish brown, long, strong setae. 



Anal legs longer than in Amphipsyche; dorsal sclerite of section "b" 

 (Figure 773) brownish yellow, with narrow, reddish brown dorsal and basal 

 margin; ventral margin pale; articular rods reddish brown, with long, thin, 

 brown, dorsal setae near base; membrane with 3 similar long, thinner, brown 

 setae, which are analogous to anal fan of Hydropsyche; outer side 

 distally and ventrally with a row of long chestnut brown setae at margin of 

 sclerite which are sparser apically and dense basally; they number 34—38; 

 there is a longitudinal group of 25—2 6 similar setae in middle; several 

 setae near base of anal leg; sparse short setae at dorsal margin and on 

 surface; membrane near sclerite "c" with a strong, long, brown seta 

 ventrally; 3 or 4 short, thin setae further basally. Sclerite "c" brown, its 

 primary seta strong, reddish brown and situated distally; 3 or 4 much 

 smaller secondary setae near margin. 



Dorsal setae 1 and 2 of the claw light and divided; seta 1 with 6 branches, 

 seta 2 with 2 branches; median seta 3 brown, moderately long; outer seta 6 

 shorter; seta 8 straight, strong, light, reaching end of claw; seta 7 small, 

 situated further basally, sometimes absent. 



Mode of life and habitats. Large rivers, Ob, Yenisei, Amur, 

 Ussuri and some lakes connected with rivers (Klyuchareva, 1952:363, 364, 

 372, 373). Large numbers of adults fly near rivers in summer. 



Distribution. Western and Eastern Siberia, Amur and Maritime 

 Territory in the USSR. In addition, West China. 



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