FIGURES 84—87. Mouthparts of microphages and phytophages of Annulipalpia: 



84 — labrum of Wormaldia subnigra; 85 — left mandible of My stro- 

 phora altaica; 86 - mandibles of Hydroptilidae: right mandible of Ortho- 

 trichia tetensii, ventral (A) , left mandible oflthytrichia lamella- 

 ris, ventral (B); 87 — larva of Ortho trichia tetensii after feeding on 

 an alga (84 - after Hickin, modified; 86 and 87 — after Nielsen). 



The larvae of Polycentropodidae, Arctopsychidae and Hydropsychinae 

 with their strong toothed mandibles (Figures 88—90) are mobile and strong 

 predators; they jump on their prey, which is often larger than themselves. 

 In an aquarium for example, the larva of Hydropsyche was observed 

 to attack a larva of Tendipes which approached its shelter; it rapidly 

 devoured the larva from the soft posterior end, leaving only the head capsule; 

 this larva also feeds on small animals and plant particles carried by the 

 current into its characteristic net (see below); in winter, when nets are not 

 59 built, the role of vegetation increases in the food of the larva; when the 

 larva is starved, it gnaws plant fragments from the wall of the case and 

 from the vicinity. In the intestine of larvae of Hydropsyche 

 (H. angustipennis, pellucidula, instabilis, fulvipes) animal 

 remains together with plant particles predominated in summer; among them 

 were heads and whole larvae of Chironomidae, larvae of Simulium, of small 

 mayflies and caddis flies (including young Rhy a c op hi 1 a), parts of caddis 

 fly pupae, mandibles and parts of legs of insects; threads of algae, fragments 

 of sphagnum, diatoms, parts of plants. It is interesting that no shrimps 

 were found in the stomach of larvae of Hydropsyche although shrimps 

 were common in their habitats; the larvae attempt to catch the shrimps but 

 cannot hold them because of their smooth and hard integument (Sattler, 

 1958:173, 176-177). 



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