509 1. Cheumatopsyche lepida Pictet 



Pictet, 1834:207, Plate XVIII, Figure l,a, b.- Siltala, 1905:108-111, 

 Figure 25.- Ulmer, 1909:235, 300, Figure 360.- Lestage, 1921:538-543.- 

 Lepneva, 1932:82-84, 108-109, Figures 1-10; 1940:206-207, Figure 154, b. 



Full-grown larva. Length 10.0—10.2 mm. Head mainly light yellow, 

 with an indistinct brownish lyre-shaped dorsal figure; frontoclypeus slightly 

 darker anteriorly and posteriorly; anterior margin mat brown, crenulate, 

 with rounded processes of different size (Figure 718); characteristic, 

 divided, small, tuftlike covering setae between the processes; tentorial pit 

 slightly dark; small, light dots in posterior angle. Clypangulus dark, 

 relatively large. Anterior-margin setae light; lateral seta as in Hydro- 

 psy c he, curved inward; intermediate seta situated nearby, larger, straight; 

 shorter median seta situated at a distance; angle of sclerite and clypangulus 

 with several secondary setae; primary frontal setae small, situated among 

 secondary setae, indistinct. Covering setae (Figure 720) situated on the 

 indistinct, brownish, lyre -shaped figure and on the frontoclypeus, mainly 

 hairlike, with long, thin end; numerous hairlike setae along frontal sutures 



510 and in posterior part thin, whitish, directed anteriorly (Figure 719); covering 

 setae sparse and very small in middle of frontoclypeus. Large, indistinct, 

 light dots on sides of posterior part of dorsal surface; following setae are 

 present lateral to frontal sutures, among the light secondary setae: straight, 

 brownish, long seta 9; near it thin light seta 11; seta 7 straight and shorter 

 than seta 9; seta 12 posterior to the eye, light brown, thick; setae 14 and 15 

 thin, light; seta 15 long, directed anteriorly; seta 16 near the suture, thick, 

 brown. Ventral side of head light without dark areas lateral to gular suture 

 characteristic of Hydropsyche; postgula forming a small, reddish brown 

 sclerite; gula fused with pregula, golden brown; anterior margin of head 

 capsule also goldenbrown. Seta 8 light yellow, straight, shorter than 7; 



seta 18 (unlike in Hydropsyche) thick, spinelike, pointed. 



Labrum (Figure 72 1) with short, lateral margin of dorsal sclerite and 

 rounded anterior margin; labrum mainly golden brown, light yellow 

 posteriorly and laterally. Covering setae with broad base and long hairlike 

 end as on the dorsal surface; primary setae among similar secondary setae 

 thin, light, some of them large. 



Mandibles (Figure 722) massive, dark brown. Upper blade of left 

 mandible with a large, projecting, apical tooth; a longitudinal row of small, 

 thin, hairlike spinules on outer side near base; lower blade of left mandible 

 with a large apical tooth and 3 smaller teeth; basal tooth large, directed 

 posteriorly; median depression with a brush of chetoids which are longer 

 posteriorly. A row of small spinules on upper blade of right mandible, on 

 outer side, near large apical tooth; 2 small teeth on lower blade near large 

 apical tooth; a 3rd, larger, basal tooth posterior to these 2 teeth, of same 

 form as on left mandible; a row of small spinules on outer side near the base 

 of this tooth. Outer setae of mandibles numerous, light; of the 2 primary 

 setae one is long, the other shorter in the apical part. 



Submentum golden brown, relatively broader than in Hydropsyche; 

 its rugose lobes short and almost in contact distally; anterior margin 

 serrated; short, light setae laterally in basal part; 3 long, light setae on 

 outer side near base; 1 of these setae primary; most secondary setae of 

 submentum short and light, some of them thin and very small. 



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