27 (22). Case different. 



28 (31). Case made of sand grains and plant particles. 



29 (so). Head and thoracic sclerites brown; frontoclypeus dark brown, 



posterior angle, spots near tentorial pits and median spot yellowish; 

 dorsal stripes distinct, with lighter space between them and 

 lateral part of head; pronotum yellowish brown, groove in anterior 

 third dark in middle; case slightly curved, narrower and rounded 

 posteriorly, made mainly of sand grains with small, smooth 

 fragments of detritus 14. L. aff inis Curt. (p. 267) 



30 (29). Head and thoracic sclerites darker; head chestnut brown, with 



small, sometimes indistinct, light spot in angle of frontoclypeus, 

 with black punctation in posterior part and lateral to coronal 

 suture; transverse groove in anterior third of pronotum broadly 

 black in middle; case slightly curved, narrower posteriorly, with 

 smooth surface, made mainly of plant particles and sand grains, the 



latter predominating before pupation 



23. L. griseus L. (p. 287) 



31 (28). Case made of sand grains. Head of uniform color, chestnut brown, 



with distinct black punctation in posterior part; frontoclypeus with 

 light posterior angle; pronotum yellowish brown, groove dark in 

 middle; case made of fine sand grains, often with a thin layer of 

 silt above sand grains, which forms a smooth, polished surface. . . 

 13. L. extricatus McL. (p. 263) 



32 (21). Dorsal side of head uniformly dark or color different. 



33 (40). Head dark or dark with a small, light spot in angle of frontoclypeus; 



groove in anterior third of pronotum with or without dark middle 

 part. 



34 (37). Primary ventral setae of mid- and hind femora forming a yellow 



spine and a thick, black seta; case made of small sand grains or 

 of sand grains and detritus, smooth, slightly curved. 



35 (36). Dorsal side of head entirely dark, without light spot; ventral 



surface also mainly dark, gula slightly dark; groove in anterior 

 third of pronotum with distinct, dark, transverse stripe in middle; 

 case smooth, narrow, markedly narrower posteriorly, made of 

 sand grains, sometimes with small pieces of detritus, its anterior 

 end with small dorsal indentation .... 16. L. vittatus Fabr. (p. 274) 



36 (35). Angle of frontoclypeus with small light spot; ventral side of head 



dark in some places, gula light; groove in anterior third of 

 pronotum slightly dark in middle; case made of sand grains, less 



smooth, less narrow posteriorly, with smooth anterior end 



15. L. centralis Curt. (p. 270) 



37 (34). Both primary ventral setae of mid- and hind femora thick, short, 



black; case made of plant particles, sometimes with a few fine 

 sand grains. 



38 (39). Larva small, 10 — 12 mm long; light spot in angle of frontoclypeus 



very small or absent; pronotum and mesonotum lighter than head; 

 posterior surface seta of fore femur situated subventrally between 

 2 primary ventral setae; case straight, smooth, made of small, 

 irregular plant particles, sometimes with a few sand grains .... 

 20. L. auricula Curt. (p. 283) 



217 



