CasCj made of sand grains, with small stones at antei'ior end, as in lai-va, 

 attachment at posterioi- end. 



Mode of life and habitats. Small, cleai" brooks with cool water. 



Distribution. Northei-n, no i^thwe stern, and central parts of the 

 European USSR. In addition, Europe, except the South. 



3. Tribe Chaetopterygini Stein 



Full-grown larva. Medium sized, 12— 16 mm long, I'arely 20 mm. Head 

 of uniform color; pattern of shades absent or little mai-ked. Head and 

 thoracic sclerites with large, distinct dots. 

 297 Anterior third of pronotum with dark sti'ipe in groove. Mesonotum 



lighter than pronotum, of uniform color, posterior angles not lightei- or only 

 slightly lighter than other surface. Anteiior sclerites of metathorax large, 

 in form of long triangles situated close together but not fused; posterior 

 part of lateral sclerites pale, slightly sclerotized, with indistinct punctation. 



Gills single, less numerous than in Stenophylacini; dorsal gills on 

 segments 5—6 and pleural gills on segments 4—5 usually absent, or thin, 

 small, sometimes present on only one side. 



Case made of sand and detritus or detritus only, rarely of sand only or 

 of fragments of live plants, sometimes of small leaves of moss. 



The larvae of this tribe are very similar and are little known; the 

 preceding characters and the following key are provisional. 



Mode of life and habitats. Running water and open shore of lake. 



Distribution. The European USSR, including the Caucasus, Altai, 

 Sayans. In addition, Europe, Iran. 



Key to Genera 

 Full-grown larva 



1 (4). Head brown or dark brown; pleural gills to abdominal segments 4—5, 



dorsal gills to segment 6; ventral gills to segment 7; case made of 

 sand grains, sand grains and detritus, or detritus only, with a rod or 

 conifer needle projecting posterioiiy. 



2 (3). Length 14— 17 mm; pleural gills to abdominal segment 4; tergite of 



segment 9 light brown, with large dots at anterior margin; case 

 often made of detritus only 2. Annitella Klap. (p. 383) 



3 (2). Length 13— 15 mm; pleural gills to abdominal segment 5; tergite of 



segnaent 9 chestnut brown or brownish, with indistinct dots; case 

 usually made mainly of sand grains, often entirely, rarely only of 

 detritus 1. Chaetopteryx Steph. (p. 374) 



4 (1). Body lighter; head yellow or yellowish brown; pleural gills to 



abdominal segment 3, dorsal gills to segment 5, ventral gills to 



segment 6; case made of detritus or fresh plant fragments 



3. Chaetopterygopsis Stein(p. 387) 



373 



