which consists of a small median spine (posterior, distoventral seta) and 

 2 small spatulate setae at the sides. 



Sclerite of abdominal segment 9 and anal legs as in A.fuscipes; claw 

 with 1 dorsal denticle. 



Larval case built of loosely connected sand grains, not as solid and thick 

 as in A. f u s c i p e s. 



Pupa. Length of male pupa 3.5— 4.7 mm; length of female pupa 5.0— 5.4 mm. 

 Antennae reaching abdominal segments 4—5; wing sheaths reaching 

 segments 5—7. Labrum and mandibles as in A.fuscipes. Number of 

 denticles on the plates of the holding apparatus as follows: IV: 7— 20+40— 80; 

 V:14— 35; VI: 10— 30; VII: 8— 20. End of body of male pupa shown in 

 Figure 387, B. 



Pupal case 4.5—6.5 mm long; stones on the dorsal side may be 

 3.5—2.8 mm. Cocoon brown, 3.5—5.0 mm long. 



Mode of life and habitats. Brooks and larger streams with 

 cool water. 



Distribution. Northwest and west of the European USSR, Caucasus. 

 In addition, Europe. 



III. Family HYDROPTILIDAE Stephens 



Full-grown larva. Small, 2.5—5.5 mm long; head and thorax of about 

 the same width; middle segments of abdomen much broader and higher than 

 thorax. Head prognathous; dorsal surface of head convex; height of head 

 increasing from the anterior margin to the middle or to the posterior third; 

 anteclypeus and labrum directed not forward as in Rhyacophilidae, but 

 slightly downward as in Glossomatinae and Agapetinae. The striking 

 character of the family is the fusion of the head sclerites in some genera, 

 in which the sutures are indistinct (A gray lea) or absent altogether, so 

 that the epicranium forms a complete capsule (Hy d r o p t i 1 a). Gula 

 triangular or undifferentiated, fused with the head capsule. Antennae 

 situated near the upper articulation of the mandible as in Integripalpia 

 (see Nielsen, 1942:272; 1948:20—22), with a slender sensilla, which is 

 sclerotized completely, except for the soft, thin-walled tip; a light seta at 

 the base of the sensilla in the middle or in distal part; this seta is several 

 times as long as the rod in some genera. Eyes relatively large, situated 

 at midlength of the head or in its anterior third. Setae of head well 

 developed; the longest (9, 12, 14, 17) are twice, three times, and sometimes 

 almost four times as long as the width of the head; ventral seta 18 some- 

 times absent (Oxyethira). 



Labrum with broad, membranous, anterior margin, sometimes 

 asymmetrical; seta 3 slightly curved inward; setae 5 and 6 longer than 

 the others, often much longer than the labrum. Mandibles asymmetrical; 

 left mandible with a deep, median depression, with teeth and processes on 

 the upper blade (sometimes also on the lower blade) and with a brush of 

 chetoids in the median notch; right mandible with a hardly marked median 

 depression or a depression absent, with one blade without teeth or with 

 small teeth; inner margin of right mandible with a small, membranous 

 part in some species of Agraylea and Hydroptila; this margin 



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