the left mandible without teeth; right mandible with a small, blunt, basal 

 tooth. Outer setae of mandibles situated nearby; basal seta longer, straight 

 and dark, distal seta shorter, light and curved. 



244 



FIGURES 240-243. Rhyacophila impar Mart.: 



240 —head, dorsal; 241 — mandibles, dorsal: left (A) and right mandible (B); 242 — anterior 

 margin of head, ventral, gula, pregula and maxillolabium; 243 — pronotum. 



257 



