Median tergites of mesonotum with indistinct dots and numerous setae 

 anteriorly and at posterior margin; lateral tergites oblong, narrow anteriorly, 

 with a light ridge with a row of setae near lateral margin; setae more 

 numerous near anterioi' angle. 



Pleurites yellowish, with black pleural groove; propleui'on similar to 

 that of Brachycentrus subnubilus; mid- and hind tibiae without 

 distoventral process. 



Tergite of abdominal segment 9 yellowish, indistinct, with numerous setae 

 in posterior part, at margin and on surface (11 — 12 secondary setae in 

 addition to primary setae). 



Claw of anal legs short, with 3 dorsal denticles. 



Pupa. Length 4.5 mm. Antennae reaching end of abdominal segment 7, 

 sheaths of fore wings to end of segment 6 or beginning of segment 7. 



Labrum (Figure 655, A) with a small light seta laterally at anterior 

 margin; 5 yellowish surface setae at end, thin. Mandibles narrower distally, 



slightly curved, without a distinct boundary 

 between apical and basal parts. Mid- 

 tarsi natatorial, with numerous setae. 

 Posterior processes of abdominal segment 1 

 brown, with black and dark brown spinules, 

 divided by a relatively wide, brown space. 

 Holding apparatus on segments 3—7; 

 number of spinules (after Siltala): 111:4—10; 

 IV:6-11; V:4-ll +20-24; VI:6-10; 

 Vll:7— 12. Lateral line with dense grayish 

 setae on segments 5—8. Gills absent. 

 Posterior segment in both sexes with small 

 ventral tubercles with 3 setae near base of 

 anal rods. 



Sheath of male genitalia distinct, large, 

 short, widely separated on sides of segment; 

 anal appendages rodlike, uniformly thin, 

 bent upward and covered with small spinules 

 (Figure 655, B). 



Case 4.5— 6.0 mm long, straight or slightly 

 curved, slightly narrower posteriorly, 

 smooth, made of fine sand grains, with a 

 yellowish or brownish membrane at each 

 end; anterior membrane with 2 holes, surrounded by a ring of darker and 

 thicker tissue; posterior membrane pale in middle and with 14—30 holes, 

 darker laterally. 



Mode of life and habitats. Clear, rapid brooks with stony 

 bottom. 



Distribution. West and northwest of the European USSR. In 

 addition. Central Europe. 



FIGURES 654 and 655. Mi erase ma 

 setiferum Pict. (after Siltala): 



654 — pronotum; 655 — pupa: antecly- 

 peus and labrum (A), posterior part of 

 male pupa, ventral (B). 



VI. Family CALAMOCERATIDAE Ulmer 



Full-grown larva. Medium-sized to large, 15— 24 mm long. Head 

 chestnut brown, with large light dots or spots; frontoclypeus narrow, with 

 shallow lateral indentations; gula small, triangular; gular suture much 



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