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Pupa. The pupa is of varying size and form, 2.2— 35 mm long. Abdominal 

 segment 1 without dorsal tubercle; gills present only in the 3 highest 

 families. Anal appendages usually lobe-shaped, short, rounded or notched 

 at the end; if the anal lobes are long, they are not very narrow and rodlike; 

 anal appendages sometimes absent. Pupae live in cavelike cases with a 

 covering of small stones or sand grains, attached to substrate with the 

 margin of the open ventral side, or in very small (3—5 mm) flattened or 

 differently shaped cases consisting of secretion or secretion-covered with 

 small sand grains attached to the substrate by ligaments which are widened 

 at the end; tubular cases of the Macronematinae in the Far East and Siberia 

 are irregular, oblong-cup-shaped, smooth walls covered with small sand 

 grains; they are attached to the substrate at the narrow anterior end. 



Mode of life and habitats. Live in running water, in various 

 types of streams, from springs and small brooks to turbulent mountain 

 streams and large rivers in the plains; a few species live in stagnant water, 

 mainly in large, clean water bodies. 



Distribution. Cosmopolitan. 



Key to Families 

 Full-grown larva 



1 (12). Large secondary setae absent on the legs; there is no dense row 



of long, thin setae on the sides of the abdomen; there is also no 

 cover of minute setae on the body; me so- and metanotum 

 membranous; if sclerotized, the larvae are small and live in cases 

 I. Superfamily Paleochaetoidea Lepn. (p. 214) 



2 (3). Larvae small, 2.5— 5.5 mm long; dorsum of all 3 thoracic segments 



sclerotized; abdomen broader and higher than head and thorax, 

 laterally compressed in most forms; tracheal gills, if present, only 

 on abdominal segment 9 and at base of claws of the anal legs. Case 

 of varying form, made of secretion, secretion and algae, secretion 

 and small mineral particles; they are usually laterally or dorso- 

 ventrally flattened III. Hydroptilidae Steph. (p. 345) 



3 (2). Larvae usually larger; pronotum sclerotized; meso- and metano- 



tum membranous; abdomen often more or less flattened dorso- 

 ventrally; gills, if present, only on abdominal segment 8; tracheal 

 gills on segment 9 absent. Larvae without case; if they live in 

 cases, the species are medium sized or small, the case is flat 

 ventrally, roof- shaped dorsally, consisting of small stones or large 

 sand grains. 



4 (7). Larvae large, medium sized or small; dorsal sclerite of abdominal 



segment 9 present; tracheal gills present or absent; larvae with 

 or without case. 



5 (6). Larvae large or medium sized; body of many forms dorsoventrally 



flattened; tracheal gills present or absent; case absent 



I. Rhyacophilidae Steph. (p. 215) 



6 (5). Larvae medium sized or small; tracheal gills absent; larvae with 



shieldlike cases II. Glossosomatidae Wall. (p. 322) 



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