Trochantin of prothorax short, fused with episternum and membranous 

 apically; seta of trochantin small, spinelike; setules situated at the sides; 

 membranous stripe dividing the epimeron broad and distinct. Each thoracic 

 segment with a median anterior sternite and two lateral posterior sternites. 



Forelegs short; midlegs and hind legs long. Femur of foreleg with a 

 basal process on which the spinelike ventral setules are situated; tibia with 

 a long distal process at the end of which the ventral setae of the tibia are 

 situated; these setae are situated close together and form thick, strong 

 spines; small spinules lateral to the process. Midlegs and hind legs long, 

 thin and straight, trochanters and femora directed upward at rest; tibiae, 

 tarsi and claws are raised above head and thorax and extended forward, 

 so that the thin end of the legs like those of the larvae of Mystacides 

 (Leptoceridae) extend from the case; claws of midlegs and hind legs with 

 a small, thin, light, dorsal spinule in addition to the basal seta. 



Abdomen laterally compressed, usually curved; 1st segment, sometimes 

 1st and 2nd segments much smaller than the others; constrictions between 

 abdominal segments not as deep as in Agraylea and Hydroptila. 

 Anal legs short; claw small, its apex strongly curved, with two small dorsal 

 denticles which bear 2—3 secondary denticles; setae 4 and 5 absent. 



Case made of secretion without algae, laterally compressed, bottle- 

 shaped. 



Young larva. Head of young larva slightly oblong; the body tapers 

 gradually posteriorly from the prothorax in the 1 st stage; the abdomen becomes 

 slightly broader only in the area of the anal legs; the middle segments of the 

 abdomen become gradually larger than the posterior segments in the 

 following stages. The mandibles of the young larva are short, the teeth are 

 clearly marked and more numerous than in the full-grown larva. The 

 thoracic segments of the early stages are longer and broader than the 

 abdominal segments; the few secondary anterior-angle setae appear from the 

 4th stage onward. Distal process of tibia of forelegs present in the 1st stage, 

 but without external spinules; midlegs and hind legs long; they are almost 

 as long as the body of the larva in the 1st stage; the difference in the length 

 of the legs becomes less in the following stages. 



The abdominal tergites are represented by a small median sclerite and 

 two very small lateral sclerites which bear the anterior -angle setae; the 

 sclerite of abdominal segment 9 is smaller than in Hydroptila, covering 

 only Is of the segment; the setae of the abdominal segments are longer 

 than those of the full-grown larva but not as long as in Agraylea and 

 Hydroptila. Anal legs moderately long; sclerite "b" of the basal segment 

 with one seta in the 1st stage, which is remarkably long (2 setae in the 

 following stage); intermediate dorsal seta of the sclerite twice as long as the 

 body of the larva in the 1st stage; it is the longest seta in the order 

 Trichoptera; the length of these setae and of the other abdominal setae 

 decreases sharply at the molt from the 4th stage to the 5th. 



Pupa. Length 2.0— 3.0 mm. Female pupae slightly larger than male 

 pupae; antennae of male pupa longer and thicker than those of female pupa, 

 reaching abdominal segment 7, those of the female pupa do not reach beyond 

 segment 3. Labrum with rounded anterior margin and anterior angles; 

 anterior -margin setae usually absent; if present (Ox. sagittifera) they 

 are little marked; posterior-margin lateral setae long; median setae very 

 small. 



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