part narrow; their end prolonged in a filament, which is curved and 

 sometimes bifid near the apex. Number of spurs 2,4,4. Presegmental 

 plates on segments 2—8 and postsegmental plates on segment 5. Lobes 

 of the last segment with 7 or 8—9 setae at the end. 



Mode of life and habitats. Running water with rapid or slow 

 current; also in the open littoral of large lakes. 



Distribution. Throughout the Soviet Union. In addition, cosmo- 

 politan, except Australia and New Zealand. 



Key to Genera 

 Full-grown larva 



1 (2). Head and pronotum yellow or yellowish brown, with light brown or 



indistinct pattern, or without pattern. Gula small, forming an 

 equilateral triangle wedged into the anterior margin of the head. 

 Submentum blackish, dark brown or reddish brown, pentagonal, with 

 a rough, tuberculate surface and a light, long median suture; each 

 half of sclerite longer than broad. Claw of anal legs with several 

 long coarse ventral spinules 3. Psychomyia Latr.(p.455) 



2 (l). Head and pronotum with distinct pattern or dark and without pattern; 



gula broadly triangular, situated outside the head capsule. Sub- 

 mentum light, dark only laterally, short and broad, with a median 

 suture; each half of sclerite much wider than long. Claw of anal 

 legs with a few ventral small spinules or without spinules. 



3 (4). Head with slightly dark dorsal stripes or dark. Mandibles in the 



greater part long 1. Tinodes Curt. (p. 441) 



4 (3). Head light, with a broad transverse dark band posteriorly, which is 



continuous or interrupted on the frontal sclerite. Mandibles 

 massive and short 2. Lype McL. (p. 450) 



394 Pupa 



l(4). End of mandibles hooklike, divided; blade of mandible straight in its 

 middle serrated part. 



2 (3). Length 4.2— 4.4 mm; presegmental spinules in small numbers: 



5—6 on segment 4, 6—8 on 6, 4—5 on 8. Anal lobes broad, short and 

 with 7 terminal setae 1. Tinodes Curt. (p.44l) 



3 (2). Length 5.5 mm; presegmental spinules more numerous: 7—9 on 



segment 4, 12—13 on 6, 8—11 on 8. Anal lobes narrow, long, with 



8 setae 3. Lype McL. (p. 450) 



4 (l). End of mandible undulately or spirally coiled, pointed; blade of 



mandible slightly convex in the middle serrated part 



2. Psychomyia Latr. (p. 455) 



1. Genus Tinodes Curtis 



Full-grown larva. Length 8— 10 mm. Head oblong, with almost parallel 

 sides. Frontoclypeus with straight anterior margin, with a transverse row 



441 



