Case 14— 16 mm long, with smooth surface, like larval case, slightly- 

 curved, made of sand grains, sometimes with small pieces of detritus, 

 rounded at end, closed with sand grains and with small holes; anterior and 

 posterior ends attached to plants. 



Mode of life and habitats. Open shore of lakes on a bottom of 

 sand or sand with stones; clear brooks with slow current. 



Distribution. Northern, central, and western parts of the European 

 USSR. In addition. Central and Northern Europe. 



14. Limnophilus af finis Curtis 



Meyer, 1867 : 160-161 . - Siltala, 1904c:50-53, Figure 11. - Ulmer, 

 1909:261.- Lestage, 1 921 : 735, 746. 



Full-grown larva." Length 14— 16 mm. Head mainly dark, orange-brown. 

 Frontoclypeus (Figure 372, A) occupied almost entirely by large, dark 

 pattern, leaving light areas as follows: posterior angle, a narrow stripe 

 laterally in middle, before and behind tentorial pit, and a large spot in 

 anterior part near median pit. Anterior margin dark reddish brown; 

 anterior part with distinct punctation, posterior part with wedge-shaped 

 punctate pattern. Dorsal stripes wide, with sharp outline laterally, close 

 to epicranial suture; lateral and dorsal stripes slightly dark, with large 

 dark dots; space between stripes lighter; a narrow, dark band behind 

 eyes. Ventral surface mainly brown, yellowish posteriorly, with large, 

 dark dots near occipital foramen, 2 larger dots at margin of dark area. 

 Quia brownish, long (Figure 372, B); large setae black; seta 14 only slightly 

 longer than seta 9; seta 15 thin; seta 17 strong, both of moderate length, 

 smaller than in the species of Limnophilus described before this. 



Labrum bright orange -brown; anterior margin with deep, curved, median 

 depression; a large, dark spot behind median pit; posterior-angle sclerites 

 short, black. Seta 1 in form of blunt, light, short spine; setae 2 and 4 

 represented by larger spines; seta 3 straight, light, short; setae 5 and 6 

 yellow, strong, larger than others, 5 slightly larger than 6. 



Mandibles black, with pinkish distal margin; left mandible with large 

 median tooth, ventral tooth distinct, 3 dorsal teeth indistinct, rounded; 

 right mandible with 5 teeth distally, subventral tooth larger than others, 



1 ventral and 3 dorsal teeth distinct, of equal size; median brushes of 

 dorsal blade tuft -shaped, consisting of light, thick chaetoids; lateral setae 

 situated basally, light dorsal seta slightly larger than ventral. 



Pronotum (Figure 373) yellowish brown; anterior third light, with fine, 

 sparse, dark punctation, middle of groove brownish; X-shaped median 

 pattern consisting of large dots, lateral groups in posterior part also 

 consisting of large dots; anterior margin with dark stripe laterally in 

 middle of each half; posterior margin wide, light in middle, with transverse, 

 black stripe laterally; posterior-angle process with dark lateral margin, with 



2 large dark dots basally. 

 Large setae thin; anterior -angle seta brown, longer than others; 



medioanal surface seta almost the same, 2nd large surface seta slightly 

 smaller; numerous, small setae in anterior third and other parts of sclerite. 



* D8scribed from 4 specimens collected in the P'yavitsa River, Moscow Region, by lordanskii in 1923. The 

 description of Siltala (1904-1906) is made from larval exuviae from case of a male pupa. Meyer 

 (1867:160—161) describes the case only; the earlier descriptions are unreliable. 



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