i7 



distinct, border absent, except the posterior angle spot, which is very large 

 in Apataniini. Metanotum without anterior and posterior median tergites; 

 lateral tergites indistinct posteriorly. 



Propleuron with small, short epimeron; mesopleuron large, darker and 

 larger than metapleuron. 



Prothoracic horn absent in some genera. 



Forelegs shorter than mid- and hind legs, in contrast to Limnophilinae. 



Dorsal and lateral processes of abdominal segment 1 low, ventral surface 

 of segment convex, padlike. Ventral elliptical areas on segments 2—7 or 

 2—8. Lateral line formed by small, light, hairlike, spinules. Gills single, 

 dorsal and ventral rows only; gills rarely absent. 



Case made of sand grains, narrower posteriorly, curved, flattened 

 dorsoventrally; surface smooth or rough, with larger sand grains laterally. 



Pupa. Length 5— 9 mm. Median blade of mandibles with characteristic 

 process, serrated apically, with dense, light, thin spinules basally. Spinose 

 dorsal processes of abdominal segment 1 situated almost laterally; lateral 

 row of gills absent. Anal rods thin, tapering posteriorly, usually crossed. 

 Case attached at anterior end; opening covered by merabrane facing 

 substrate, leaving a crescent -shaped stripe with holes; membrane at 

 posterior end covered with sand grains, with several holes. 



Mode of life and habitats. Cool, clear, running water, springs, 

 mountain brooks and rivulets, in littoral zone of large rivers, open 

 shore of lakes. 



Distribution. The European and Asiatic parts of the USSR. In 

 addition, Europe, Asia, North America. 



Key to Tribes* 

 Full-grown larva 



1 (2). Medium-sized, 10— 15 mm long, rarely 17— 18 mm. Submentum 



without median sclerites. Hairlike, light chaetoids in ventral part 



of trochanter or in basal part of femur absent. Gills present on 



segments 2—3, rarely on 2—4, or only on segment 2, usually 



postsegmental; one genus also with dorsal presegmental gills. 



Lake Baikal 1. Baicalinini Mart. (p. 104) 



2 (l). Usually small, 6— 9 mm long, rarely 10—11 mm. Submentum with 



median sclerites. Hairlike, light chaetoids present in ventral distal 

 part of trochanter of fore- and hind legs and in basal part of fore 

 femora. Presegmental and postsegmental gills on segments 1—6. 

 Widely distributed 2. Apataniini Ulm. (p. 134) 



1. Tribe Baicalinini Martynov (Thamastini Schmid) 



See Schmid, 1953:110, 1955:77; Lepneva, 1964:670 for tribe Baicalini. 

 Full-grown larva. Length 9— 16 mm. Head markedly narrower than 

 pronotum, slightly oblong, directed downward and slightly posteriorly. 



The subfamily contains 3 tribes, of which 2 occur in the USSR; the 3rd tribe, Moropsychini, is distributed in 

 Japan, Burma, Assam, and India (Schmid, 1954:6.0—71). 



104 



