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7. Genus As yn ar c hu s iVIcLachlan 



Full-grown larva. Length 15—23 mm. Body light. Main color yellow^ 

 dark areas poorly differentiated; large setae black or dark brown. Dorsal 

 pattern of head resembling that of larvae of Anabolia but lighter. Legs 

 light brown, with distinct dark punctation. Tergite of abdominal segment 9 

 pale, without secondary surface setae; 1 — 2 setae sometimes between 

 medioanal setae. Claw of anal legs with 2 dorsal denticles. 



Case made of detritus, straight, slightly narrower posteriorly, some- 

 times with long rods projecting at ends. 



Mode of life and habitats. Usually in stagnant water, in slow 

 parts of brooks and rivulets, in lakes and puddles of river floodplains, in 

 littoral of lakes. 



Distribution. Northern part of the European USSR, Siberia, Mari- 

 time Territory, Amur Region. In addition. Northern Europe, Mongolia, Japan, 

 North America. 



Key to Species 

 Full-grown larva 



1 (2). Body light; anterior part of frontoclypeus slightly dark only in 



middle; a dark, very narrow stripe lateral to frontal suturies and 

 coronal suture; tergite segment 9 without secondary seta between 

 medioanal setae; claw of anal legs with 2 large dorsal denticles; 



case usually with long rods projecting at ends 



1. A. amurensis Ulm. (p. 307) 



2 (1). Body less light; dark area in anterior part of frontoclypeus wider 



than in A. amurensis, sometimes entire anterior part grayish 

 brown; stripes lateral to epicranial suture darker and broader; 

 claw of anal legs with dorsal denticles of different size; case 

 without long, projecting rods ... 2. A. lapponicus Zett. (p. 31l) 



1. Asynarchus amurensis Ulmer, larva nova 



Full-grown larva. Length 22 — 23 mm. Dorsal pattern on head resembling 

 that of larvae of Anabolia but lighter. Frontoclypeus (Figure 431, A) 

 slightly dark at anterior margin; median pit with large, reddish brown, 

 laterally concave spots on each side as in A. nervosa; median space 

 between spots slightly dark; brown spots near tentorial pits, margin of 

 sclerite with a narrow, brownish stripe near suture posteriorly; wedge- 

 shaped pattern distinct, light in middle, area between pattern and stripes 

 always light, which is characteristic for larvae of Asynarchus. 

 Sclerite narrowly brown on area of dorsal stripes, from tentorial pit 

 along frontal sutures and beginning of coronal suture; short transverse 

 rows and groups of dots lateral to stripes; space between dorsal and lateral 

 stripes light; rows of dots on area of lateral stripes; area anterior to eye 

 dark, as in Anabolia. Ventral surface with large, dark spots in middle, 

 and a group of dots behind spot near occipital foramen; a narrow, dark 

 brown stripe along gular suture. Gula brown, long (Figure 431, B). 



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