subapical tooth; lower blade with the serrated part common in species of 

 Rhyacophila; subapical tooth of upper blade of right mandible smaller 

 than that of left mandible; lower blade with a large blunt basal tooth; outer 

 setae long; distal seta curved. 



(272) 



FIGURE 297. Rhyacophila obscura Mart. Full-grown larva, lateral 



Maxillolabium shown in Figure 300. 



Pronotum brown, shorter in the middle than laterally (Figure 30l); 

 anterior margin without a dark border; posterior margin narrow and 

 black, with a broad process in the middle of each half; a second small 

 process near the median suture; posterior angles black, with short 

 processes; lateral margin with a dark border in posterior half, but without 

 border in the anterior part. The primary seta of the anterior -angle 

 depression and one of the secondary setae long and black, longer than the 

 sclerite; the 2nd secondary anterior -angle seta between them is very 

 small, as in Rhyacophila s. str.; anterior angle with 3 small setae 



292 



