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Larvae of species of Limnophilidae build cases from live plants, including 

 the genera Glyphotaelius and Nemotaulius (G. pellucidus, 

 N. punctatolineatus). The cases of these species are straight tubes 



which are dorsally and ventrally 

 covered with large, laterally projecting 

 plant fragments; these fragments are 

 arranged and cut in such a manner 

 that the case looks like the leaf of a 

 plant; the larvae build their cases of 

 the leaves of Potamogeton natans, 

 but they also use other plants. The 

 type of the structure changes with age. 

 The larvae of the early stages build the 

 outer layer of the upper and lower sides 

 of the case from narrow, thin fragments 

 of sedge which are placed transversely 

 (Figure 112, A). As the larvae grow, 

 they use fragments of large leaves; 

 the anterior margin of a fragment is 

 convex and its posterior margin 

 slightly oval or straight; the fragments 

 are arranged alternately, either on the 

 dorsal or on the ventral side at the 

 anterior margin of the case. The part 

 of the case with broad fragments 

 increases gradually, and the empty 

 case of the younger stage remains 

 attached posteriorly (Figure 112, C); 

 it falls off after some time and the case 

 of Nemotaulius acquires its 

 definite shape which is characteristic 

 for the larvae of older stages 

 (Figure 112, D). The broad fragments 

 on the dorsal and ventral surface are 

 contiguous at the sides and between 

 the margins, and the lateral wall of the 

 tube remains a free space. The cases 

 lose their green color toward autumn: the larvae move to the bottom and 

 new fragments of fallen leaves are added; the case becomes dark, like other 

 animals living on the detritus-covered bottom. 



An example of cases built of detritus are those of the larvae of Limno - 

 philus,e.g., L. f la vie o rn i s, L. politus, L, rhombicus, L. mar- 

 mo r a t u s and partly also of those of L.nigriceps; the larvae of this 

 species build their cases from detritus in the early stages and, in later 

 stages, they build them from fragments of live plants. The freshly hatched 

 larvae of L. nigriceps leave the egg mass and build a temporary case; 

 a ring around the first abdominal segments is built first; it is continued 

 posteriorly and the whole abdomen of the larva is gradually covered with 

 the case, which is irregularly covered with detritus (Figure 113); only then 

 does the larva begin to feed. 



FIGURE 112. Construction of the case of Nemo- 

 taulius punctatolineatus: case of a young 

 larva (A), case covered with spheres of Nostoc 

 (B), case of a 4- stage larva with remains of the 

 case of the preceding stage (C), case of a full- 

 grown larva, dorsal (D) 



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