apical part of mandible covered with tubercles, which occupy more than half 

 its length; basal part convex, less broad than in P. c o n s p e r s a. 



Wing sheaths extending to abdominal segment 4. Natatorial setae on 

 segments 1 and 2 of mid-tarsi; unlike in P. c on s p e r s a, they are present 

 on the dorsoventral side of both segments; ventral setae of second segment 

 very small. 



Presegmental plates of holding apparatus present on abdominal 

 segments 3—8, postsegmental plates on segment 5; number of spinules as 

 follows: 111:4; IV:4; V:4 + 7; VI:6; VII:4; VIII:5; plates concave like cups; 

 432 spinules present at distal end of plate. Segment 2 with only one dorsal gill 

 filament; segment 3 with two equal filaments, one dorsal and one ventral; 

 dorsal filament on segments 4—7 shorter than ventral filament; dorsal 

 filament on segment 7 only about half as long as ventral filament. 



Anal lobes broadly oval, with numerous black or brownish black setae; 

 ventral median process of abdominal segment 8 of female pupae slightly 

 longer than in P. c o n s p e r s a, with an apical saddle -shaped indentation. 



Length of pupal case 23—30 mm, width 8—9 mm; walls covered with 

 detritus; ventral surface covered with grayish tissue. Pupa lying in a 

 cocoon of loose tissue. 



Mode of life and habitats. Mountain rivulets, brooks and springs, 

 in various biotopes, on stones and among stones, on the usually stony bottom. 



Distribution. USSR: Ciscaucasia, the Central Caucasus, Trans- 

 caucasia. In addition, Iran. 



2. Genus Polycentropus Curtis 



Full-grown larva. Length 12—14 mm. Head oblong, with almost parallel 

 sides; head light yellow, with distinct punctate and shaded pattern. Labrum 

 without pattern; setae thin. Pronotum with characteristic but not always 

 distinct dots; dark brown posterior margin relatively narrow; anterior- 

 angle seta strong, much shorter than anterior -margin setae. Tarsi, 

 especially on the forelegs, short; claws thin, slightly curved, longer than 

 tarsi; ventrodistal setae of tibiae long, dark, spinelike, thick, almost reaching 

 base of claw; tarsi of forelegs with dense thin feathered setae near the apex. 

 Dorsal setae on sides of segment 9 small, smoke brown; a small indentation 

 laterally; sclerite with a long medioanal seta, a small intermediate seta and 

 a short lateral seta near the sclerite. Anterior -angle seta indistinguishable, 

 setuliform. Anal legs long; section "a" longer and broader than section "b"; 

 transverse stripe in the distal quarter little marked; dorsolateral sclerite 

 of section "b" usually light, with or without indistinct dots; primary disto- 

 dorsal setae long, dark; secondary setae numerous. Claw thin, long, bent at 

 almost a right angle; spinules of ventral comb very small; 1—2 longer 

 spinules on the distal band, projecting above the claw, giving the impression 

 of a dorsal denticle as was erroneously described and illustrated by Siltala 

 (l903c:12, Figure 4, a) and Ulmer (1909:230, Figure 353, d). 



Pupa. Length 6—8 mm. Antennae of male pupae reaching end of 

 abdomen; those of female pupae segment 6. Clypeus with 2 long setae and 

 a short lateral seta on each side; labrum with 2 long and 4 short setae; 

 setae longer than in Plectrocnemia. 



