Case made of plant or mineral particles. 



Mode of life and habitats. Brackish lakes; coastal waters of the 

 Gulf of Finland. 



Distribution. USSR: European part, northern, northwestern, and 

 southwestern areas. Middle Asia. In addition, Mongolia. 



1. Agrypnetes crassicornis McLachlan 



Siltala, 1904c: 19-25, Fig. 5; 1907:443-444. 



Full-grown larva. Length 16— 20mm. Coloration very variable; Siltala 

 (1904:19—25) described dark larvae of greater size (length 20— 25 mm) from 

 the coastal zone of the Gulf of Finland, with a wide, dark pattern on the 

 frontoclypeus and with wide, partly fused dorsal and lateral stripes on the 

 head. Light specimens from the Aral Sea, Lake Uruskul in the Central 

 Urals and lakes of Eastern Siberia are in the collection of the Zoological 

 Institute of the USSR Academy of Sciences. The dark variety described 

 by Siltala is characteristic of the population at the western border of the 

 range of A. crassicornis. 



FIGURES 20— 22. Agrypnetes c ra ss ic orn is McL.: 



20 — head, dorsal (A) and ventral (B); 21 — labrum; 22 —mandibles, 

 dorsal, left (A) and right (B). 



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