usually on a bottom of stone, sand and stone, pebble, or sand; rarely in the 

 sublittoral, to a depth of 30 m in Lake Teletskoe, to 7 m or slightly deeper 

 in Karelian lakes. 



Distribution. Throughout the USSR. In addition, Europe, China, 

 Japan, Mongolia, Pakistan, Assam, Burma, North America. 



Key to Species 

 Full-grown larva 



1 (8). Head blackish, dark brown, or brown; gula wide, short, or oblong- 



heart-shaped; seta 15 much shorter, thinner, and usually lighter 

 than 14; ventral gills present on segment 6. 



2 (7). Head blackish or dark brown; gula short, wide, almost as long as 



wide; if present, gills of abdominal segment 1 only dorsal. 



3 (4). Head blackish; large setae 9 and 14 black; gula short oval; gills 



present on abdominal segment 1 5. A. zonella Zett. (p. 158) 



4 (3). Head and large setae 9 and 14 dark brown or chestnut brown; gula 



of different form; gills of abdominal segment 1 present or absent. 



5 (6). Gula triangular, with straight or almost straight sides; dorsal gills 



of abdominal segment 1 usually present, sometimes absent; ventral 



gills present on segments 6 and 7; Middle Asia 



7. A. copiosa McL.(p. 167) 



6 (5). Gula with curved sides; dorsal gills absent on abdominal segment 



1; ventral gills only on segment 6; Europe 



8. A.muliebris McL.(p. 171) 



7 (2). Head brown; gula large, oblong-heart-shaped, with truncate or 



bluntly rounded posterior end; northern species 



6. A.majuscula McL. (p. 162) 



8(1). Head brown, rarely dark or light brown; gula narrow, oblong; 



seta 15 smaller than 14 or almost as long; abdominal segment 6 



with or without gills. 

 9 (12). Head dark brown, chestnut brown, or brown; gula very narrow; 



gills absent on abdominal segment 1 . 



10 (11). Head dark brown or brown; seta 15 much shorter than 14; gills 



present on abdominal segment 6; Caucasus 



2. A. subtilis Mart. (p. 142) 



11 (10). Head chestnut brown; seta 15 moderately long, only slightly smaller 



than 14; abdominal segment 6 with or without gills; Siberia 



JJ2 • 3. A.crymophyla McL. (p. 148) 



12 (9). Head light brown; gula wider; gills on segments 1 and 6 present 



or absent; mainly a northern species. 



13 (14). Gills absent on abdominal segments 1 and 6. 



14 (13). Gills present on abdominal segmients 1 and 6. 



15 (I6). Gula with curved sides; seta 15 markedly shorter than 14 



4. A. stigmatella Zett. (p. 153) 



16 (15). Gula oblong-triangular, with straight sides; seta 15 long, almost 



as long as 14 9. A. auricula Forssl. (p. 175) 



136 



