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Mandibles with a broad, massive, basal part and a narrow, long, pointed, 

 apical part which is serrate-denticulate on the inner side. 



Wing sheaths pointed and long; they reach the end of the abdomen or 

 beyond it. Dorsal row of natatorial setae present on the segments 1—3 of 

 the mid-tarsi, ventral row on segments 1—2. 



Abdomen spindle-shaped; pre segmental plates of holding apparatus 

 oblong and situated on segments 3—7; their posteriorly-directed spines are 

 few in number, large, forming a longitudinal row; postsegmental plates 

 rounded; the anteriorly-directed spines on segments 3—5 are slightly 

 smaller than on the presegmental plates. 



The pupal case is the modified, closed, larval case attached to the 

 substrate; it is always attached to the substrate with its broad side; the 

 attachment ligaments are situated at the corners of the broad end of the 

 case and at the sides of the neck. The pupa lies in the case with its head 

 toward the broad end and with its dorsum toward the substrate; the broad 

 end of the pupal case thus becomes the anterior end; the side toward the 

 substrate becomes the dorsal side and the outer the ventral side; the neck 

 of the case appears dark, because the exuviae of the last molt are contained 

 there. The case is closed anteriorly, with a curved, narrow membrane; 

 the neck is covered posteriorly with a mesh of threads which form a plug 

 sometimes projecting beyond the neck or situated at a distance from 

 it. The pupa is immobile. The ligaments form disks which are attached 

 to the substrate; the disks consist of a tangle of filaments arranged radially 

 or irregularly; there may be one ligament at the corners with one or two 

 terminal disks, or two ligaments each with one disk; the posterior disks of 

 the neck are situated close together; they are sometimes replaced by a 

 larger median disk. They are usually situated on aquatic plants, sometimes 

 on pieces of wood or stones; in an aquarium without a suitable substrate, 

 the cases are attached to the walls, which facilitates observation of the 

 attachment and closing of the case, and observation of the prepupa, pupation and 

 the change of coloration; the pupa is at first green; it becomes darker 

 before hatching. 



Mode of life and habitats. Mainly in plant thickets in stagnant 

 water or water bodies with a slow current. 



Distribution. European USSR, Northern Caucasus. In addition, 

 Europe, Africa, India, Sunda Islands, Australia, North and South America. 



Key to Species 

 Full-grown larva 



1 (8). Outer side of distal process of fore tibia with a brush of short, 



dark spinules. 



2 (7). Dorsal surface of head between the eyes with two dark spots at the 



base of the mediolateral frontal setae; head yellow or brownish; 

 both blades of left mandible with equal or almost equal small 

 denticles. 



3 (6). Antennal seta situated in the middle of the sensilla. 



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