Anal rods (Figure 717) slightly shorter than in the preceding species, 

 with strong, black, outer setae. Genital appendages of male pupae slightly 

 curved; inner sides almost straight; penis sheath divided into 2 short, 

 broad, rounded lobes. 



Mode of life and habitats. Larvae predacious, weaving capturing 

 nets; live on solid bottom, often on stones and wood. They occur in rivers 

 and rivulets with rapids in hills and foothills, as well as in larger streams. 

 They are known from the Neva, rivulets in Karelia, Kola Peninsula, Northern 

 Urals and Upper Pechora; they are abundant in the Biya and Yenisei and its 

 tributaries (Mana, Kacha, Angara, Stony- and Lower Tunguska), rivulets in 

 the Western Sayan (Greater Kebezh, Lesser Kebezh); they often occur 

 together with Arctopsyche ladogensis Kol. 



Distribution. Mainly Eastern and Western Siberia, Altai, Sayans, 

 Kamchatka, northeast and north of the European USSR. In addition, Finland, 

 Scandinavia. 



2. Genus Cheumatopsyche Wallengren 



Full-grown larva. Smaller than larva of Hydropsyche; length at 

 most 10.0—10.5 mm. Sclerotized parts of body yellowish; pattern pale, 

 indistinct. Head as in Hy d r o p sy c h e, short and broad; frontoclypeus 

 of same form. Covering setae small, sparse, setuliform and hairlike, 

 rarely blunt. 



Mandibles shorter than in Hydropsyche, broad in basal part; basal 

 tooth characteristic, differing from that of H y d r o p s y c h e, its apex 

 directed posteriorly. In addition to median brush of left mandible, apical 

 part with a row of small hairlike spinules on outer side of left and right 

 mandible. 



Narrow median black spot at posterior margin of mesonotum; median 

 spot of metanotum small, dot- shaped. 



Number of gill filaments smaller than in Hydropsyche. Distodorsal 

 tuft of setae of anal legs less dense than in Hydropsyche. 



Pupa. Length 6.0— 6.5 mm. Antennae of male pupae shorter than in 

 Hydropsyche, not curved at the end. Crotchets on plates of holding 

 apparatus less numerous than in Hydropsyche; postsegmental plates 

 smaller and of different form. 



Genital appendages of male pupae shorter and broader than in Hydro - 

 psyche, pointed at inner side of end; penis sheath short and broad. 



Pupal case to 10 mm long, made of sand grains, small stones or detritus. 



Mode of life and habitats. Larva predacious, building small 

 capturing chambers as does Hydropsyche. They live in rivers, avoid 

 large, calm rivers in the plains (not found in the Volga, Dnieper or Ob); they 

 often occur in large and small rivers and rivulets with many rapids in the 

 foothills. 



Distribution. Northwest (rare), west, southwest and south of the 

 European USSR, Caucasus, Middle Asia; southern and Eastern Siberia 

 (Yenisei basin), Amur Region, Maritime Territory. In addition, Europe, 

 Africa, Asia, North America, Australia. 



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