1. Genus Lepidostoma Rambur 



Full-grown larva. Length 9—11 mm. Head and pronotum light brown 

 or brown, with distinct, rounded, or oblong, light dots. Mesonotum light 

 posteriorly. Metanotum with 3 pairs of small tergites. Setae of medium 

 length, brown or dark brown; very large setae absent; secondary setae 

 absent on head, a few present on dorsum of thorax. Forelegs short, 

 massive; nnid- and hind legs thin, moderately long; secondary setae only 

 on coxae. 



Gills on the segments 2—7. 



Claw of anal legs with one large, dorsal, and one small denticle. 



Case made of detritus, tetrahedral; rarely of sand grains, conical, straight. 



Mode of life and habitats. Small, running, water bodies, clear 

 brooks and rivulets in mountains and plains; near banks of large rivers. 



Distribution. European and Asiatic parts of the USSR. In addition, 

 Europe, North America, and parts of South America, 



1. Lepidostoma hirtum Fabricius 



Kolenati, 1848:99.- Klapalek, 1893:75-79, Figure 20.- Struck, 1900:23, 

 Figure 29; 1903:108, Plate II, Figure 15.- Ulmer, 1903:90-91, Figure 55.- 

 Siltala, 1905:29-32, Figure 8; 1907:544-549.- Ulmer, 1909:274-275, 315, 

 317-318, Figures 411-412,462.- Lestage, 1921:897-904, Figures 319-322.- 

 Lepneva, 1940:216-217, Figures 160/20.- Hickin, 1943:15-17, Figures 1-10.- 

 Brindle, 1964:197, 198. 



Full-grown larva. Length 9—11 mm. Head (Figure 60 1) slightly longer 

 than wide; antenna situated near anterior margin of light periocular spot; 

 dorsal surface uniformly brown, bright, with large, distinct, transverse or 

 rounded, light spots; brown surface with dense, brownish, microscopic 

 spinules; light spots smooth. Frontoclypeus with wide, reddish brown, 

 anterior margin; anterior part with 2 pairs of small, light dots; 1 or 2 dots 

 between tentorial pits; posterior part with a transverse row of 4 light dots, 

 2 large dots in middle, a small dot on each side; a small, distinct, and 

 2 smaller, indistinct dots at anterior end in middle. A nunnber of light, trans- 

 verse streaks or 2 oblong dots, one rounded, the other elongate, lateral to 

 epicranial suture, from seta 14; similar but smaller dots lateral to coronal 

 suture; light, rounded, smaller dots behind eye on sides. Ventral surface 

 with reticulate striation, its posterior part with groups of large, light, oblong 

 dots in each half. Gula triangular, with curved sides, slightly narrower 

 anteriorly; pregula in form of a reddish brown, transverse plate, not wider 

 than gula (Figure 601, C). 



Median and intermediate anterior- margin setae brown, relatively thick, 

 latter moderately long, former smaller; lateral anterior-margin seta light, 

 large, longer than median, procumbent; anterior frontal seta large, 

 moderately long, similar to lateral seta, light, curved inward, opposite setae 

 crossing; intermediate frontal seta situated near tentorial pit, short, thin; 

 posterior frontal seta, slightly larger, situated close to posterior margin 

 351 behind transverse row of dots. Seta 7 brown, moderately long, larger than 

 median seta, situated near margin; seta 9 situated medial to antenna, long. 



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