365 The pupal case is a slightly modified larval case directed to the substrate 

 with its broad ventral side; it has posteriorly a median single ligament 

 which is broadened into a small attachment disk at the end; the pupal case is 

 prolonged anteriorly (Figure 491 ) into a fingerlike, slightly curved tube; this 

 tube opens on the wide attachment disk of the anterior end. 



Mode of life and habitats. Running water, brooks and rivulets 

 in plant thickets. 



Distribution. Northwest, west and central belt of the European 

 USSR. In addition, Europe. 



7. Genus Stactobia McLachlan 



Full-grown larva. Small larvae with dark sclerites. Sensilla of antennae 

 long, with a seta near the apex; labrum slightly oblong. Legs relatively 

 short, differing little in length; claws long, almost as long as the tarsus. 

 Abdominal segments with dark, transverse tergites. 



Case irregularly barrel-shaped, more convex dorsally, made of secretion 

 with a few fine sand grains. 



Pupa. Length about 2 mm. Antennae short, not reaching beyond the 

 anterior segments of the abdomen. Labrum short; median process of 

 anterior margin of labrum blunt. Mandibles with smooth blades without 

 serration. Wing sheaths pointed, reaching the end of the body or slightly 

 beyond it. Holding apparatus present on abdominal segments 3—7. 



Anterior and posterior end of pupal case attached by medially situated 

 disks. 



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

 springs. 



Distribution. European USSR, Middle Asia. In addition, Europe. 



Key to Species 

 Full-grown larva 



1 (2). Dorsal side of case only slightly more convex than ventral side; 



case completely covered with a thin layer of fine sand grains .... 

 1. S. eatoniella McL. (p. 406) 



2 (l). Dorsal side of case markedly more convex than ventral side, with 



three longitudinal ribs; ventral side of case without sand grains . . 

 2. S. fuscicornis Scheider (p. 408) 



1. Stactobia eatoniella McLachlan 



Klapalek, 1901:73-76, Figures 3-11.- Ulmer, 1903:136; 1909:223, 292. 

 Thienemann, 1904b: 261, Figure 19.- Lestage, 1921 :452-455. 



Full-grown larva. Larvae small, 2.2— 2.5 mm long; sclerotized parts 

 dark. Head oblong, slightly narrower anteriorly, blackish brown; eyes 



406 



