anterior angles indistinct, with 5 dark setae situated close together on each 

 side of labrum. Mandibles (Figure 555) with broad base, a long middle part 

 and apex prolonged in a filament; apex hooklike, divided into 4 denticles; 

 2 small subapical spinules and an indistinct subapical denticle; outer setae 

 straight, short, situated close together, almost of the same length. 



Wing sheaths pointed, reaching end of abdominal segment 5, in male pupae, 

 end of segment 6 in female pupae. Natatorial setae on mid-tarsi yellowish 

 brown. 



Presegmental plates present on abdominal segments 2—8, postsegmental 

 plates on segment 5; presegmental plates small; spinules on them few, 

 numbers as follows: 11:4-5; 111:5-6; IV:5-6; V:6-5; VI: 6-8; VII:5-6; 

 VIII:4— 5; postsegmental plates thin, transverse; large and small spinules 

 forming combs and directed anteriorly near their posterior margin; 

 spinules 18—20 (rarely 12—13) in number. Last abdominal segment of male 

 pupae with two long lobes (Figure 55 6); each lobe divided into a longer 

 outer part with 7 setae, and a shorter inner broader part with small 

 spinules; last segment of female pupa long, slightly flattened at the end, 

 divided into 2 short lobes; each lobe with 2 apical processes, a shorter outer 

 process with 7 setae and a longer inner process with fine spinules 

 (Figure 557). 



Pupal case made of loose tissue and covered with fine sand grains; 

 case 5.5— 6.0 mm long. 



Mode of life and habitats. The larvae build tunnel- shaped 

 galleries; they are detritophagous and live in rapid rivulets, on stones. 



Distribution. USSR: western boundary area. In addition, Central 

 and southern Europe. 



3. Tinodes pallidula McLachlan 



Hickin, 1950:103-106, Figures 1-9. 



Full-grown larva. Length 8 mm, breadth 1.4 mm. Head (Figure 558) 

 shorter and broader than in the preceding species, mainly dark brown; 

 eyes situated on a wide light area. Frontoclypeus dark brown, slightly 

 darker posteriorly, with 3 light dots. Head dark brown posteriorly and 

 ventrally on both sides of the epicranial suture, except on a small anterior 

 stripe; a large light dot lateral to the gular suture. Setae as in 

 T. w a e n e r i. 



Labrum yellowish brown dorsally, with dark spots near the posterior 

 angles; setae 2 and 5 situated farther from the anterior margin than in 

 T. w a ene r i. 



Left mandible, with a broad blunt tooth, in addition to apical tooth of 

 upper blade; distal margin of lower blade projecting; median depression 

 with a row of short and long chetoids; right mandible with coarse serrations 

 on the blade; molar tooth of left mandible larger than that of right mandible; 

 basal outer seta longer than the other (Figure 559). 



Submentum shorter and broader than in T. waeneri; ligula less long 

 (Figure 560). 



Pronotum (Figure 56l) dark brown; surface setae nearest to the median 

 suture situated on light dots. Meso- and metathorax, setae and pleural 

 sclerites and legs as in the preceding species. 



449 



