on a membrane, reddish brown; the free trochantin short and conical, with a 

 dark brown sclerite; seta situated on the membranous apex, on a separate 

 sclerotized dot; both setules dark and situated on a membrane. Pleurites 

 of meso- and metathorax (Figure 330, B and C) (unlike in Rhyacophila) 

 in the episternal-epimeral section are arranged as on the pleuron of the 

 prothorax; the only difference is that the epimeral part of the meso- and meta- 

 pleuron is larger than the episternal part and the seta of the epimeron is 

 situated on a membrane, and is small, thin and dark; sclerite of trochantin 

 of both segments (unlike in Rhyacophila) not fused with episternum, 

 differentiated in form of a small oblong plate; seta of trochantin light brown 

 and strong, situated near the posterior margin of the sclerite; both setules 

 situated distally. 



Legs (Figures 324, 33 1) short, very similar in size and form; the fore- 

 legs slightly longer than midlegs and hind legs; chaetotaxy of the legs, 

 except the dorsal setae of the coxa, also similar; most setae are short; some 

 of them thick; ventral setae partly reduced in size. 



Coxae of all legs short, with a broad distodorsal notch on a small 

 projecting membranous distoventral part; coxae with a narrow reddish 

 brown border dorsally at the base. Anterodorsal setae of coxa of the 

 forelegs dark brown and strong; basal seta longer than distal seta; disto- 

 dorsal seta of midlegs and hind legs forms a massive brownish spine; 

 basodorsal seta short, thin and yellow; both anterior setae small, dark, 

 strong; posterodorsal seta brown and short, displaced to the posterior part 



289 of the coxa; anteroventral seta situated at the apex of an inflated 

 membranous area, small, light, larger on forelegs than on midlegs and hind 

 legs; posteroventral seta the same, but unlike in Rhyacophila, situated 

 distinctly further basally, in about midlength of the segment. Basal 

 margin of coxa with 4 setules: 2 dorsal, 1 anterior and 1 posterior. 



Trochanter short, not closed dorsally; its distal part with a wide rounded 

 membranous ventral area covered with a dense brush of minute, light 

 spinules; basal margin reddish brown; anterodorsal angle pointed, with a 

 dark setule. Anterior and posterior setae short; the former thick and 

 brown, the latter lighter, thin and curved; trochanter with three setae 

 ventrally: a relatively long, light posterior subapical seta on the membrane 

 (on a sclerotized dot); a second, posterior seta situated further basally, also 

 situated on a membrane; this seta is very small, but thicker than a setule, 

 blunt, light and hardly distinguishable among the chetoids; an anterobasal 

 seta situated near the suture; it is small and dark. 



Femur broadly membranous ventrally, with four large spots without 

 setae posteriorly and dorsally. Distodorsal seta light, short, curved 

 posteriorly, brown, spinelike, smaller and thinner on the forelegs than on the 

 midlegs and hind legs; posterior and anterior setae short and brownish; the 

 former thin and situated subapically; the latter spinelike, situated sub- 

 ventrally near the distal margin on the forelegs, situated further basally on 

 midlegs and hind legs, closer to the middle of the femur; posteroventral 

 seta situated on a membrane near the margin of the sclerite, yellowish, 

 strong, pointed and situated in about the middle of the segment; antero- 

 ventral seta situated further basally, very small, light and hardly visible 

 among the small covering chetoids. 



290 Tibia dorsally with large light spots without setae; all 6 setae are 

 situated dorsally near the apex, at the sides and ventrally; both dorsal setae 



313 



