349 Maxillolabium as in Figure 599. Paired sclerites of submentum brown, 

 with a moderately long, thick, distal seta; median sclerite small, lighter. 



(348) 



FIGURES 597-600. Lithax i nc a nu s Hag. (after Sykora): 



597 - head, dorsal; 598 - mandibles, ventral: right (A) and left (B) man- 

 dible; 599 — maxillolabium; 600 — thoracic segments, lateral. 



Pronotum (Figure 600) yellowish brown; anterior-angle process and 

 stripe near anterior margin slightly darker; posterior part with distinct 

 spots laterally near median margin; surface with large, flat tubercles; 

 6 primary and secondary setae at anterior angle, 13—22 on surface, 18 at 

 anterior margin. Tergites of mesonotum yellowish brown; median tergite 

 with large and small tubercles, and 5 dark spots laterally; anterior lateral 

 tergite with large tubercles at anterior margin; posterior lateral tergite 

 with black posterior and lateral margin; number of setae, including 

 primary setae, about 80. Four tergites on metanotum (Figure 600) brownish; 

 large lateral tergite with spinules in anterior part; smooth posterior part 

 with a light spot surrounded by spinules; 120—130 setae on, and about 

 30 setae between sclerites. 



Legs as in S. n i g r i c o r n i s, with fewer secondary setae. 



Lateral line little marked. 



Case slightly curved, made of sand grains, with 3 small stones on each 

 side, anterior stone the largest, posterior the smallest. 



Pupa. Resembling pupae of Silo. Labrum with black setae. Plates 

 of holding apparatus, lighter than in L. o b s c u r u s; number of spinules: 

 111:2-3; IV:2; V:2-3 + 8-ll; VI:2-3; VII:l-2. 



Anterior stones of case larger than in Silo. 



Mode of life and habitats. Mountain brooks and rivulets. 



Distribution. USSR: The Caucasus. Not recorded outside the USSR. 



436 



