those of the preceding segments; the dark medioanal seta and the thin 

 intermediate seta are long; all 4 setae are situated on a small, transverse 

 yellow sclerite in the posterior part of the segment. In this respect they 

 resemble the setae of the posterior margin of the dorsal sclerite of 

 abdominal segment 9. Pleural setae small, situated at the base of the gill as 

 in Rhyacophila s. str. 



254 



FIGURES 262— 265. Rhyacophila retracta Mart.: 



262 — abdominal segments 7—9 and part of the anal legs, ventral; 263 - left 

 anal leg and base of claw, dorsal; 264 — left anal leg, lateral; 265 — claw of 

 left anal leg, inner side. 



Posterior margin of dorsal sclerite of segment 9 straight, with a small 

 notch in the middle (Figure 261 ); anterior angles rounded; the anterior 

 margin has a brownish red border which is broader in the middle; two 



270 



