developed, as in all the 3 lower families of Annulipalpia, which relates them 

 to the Integripalpia; the anal legs are shorter than in the Rhyacophilidae 

 with a downward-directed claw. Unlike the larvae of Rhyacophila, 

 which can swim, the larvae of Glossosomatidae with their heavy portable 

 case are not very mobile; they live on stones among algae on which they 

 feed. 



The family Hydroptilidae is isolated from the 2 foregoing families in the 

 morphology of the larvae. The larvae of Hydroptilidae resemble those of 

 Glossosomatidae in several characters such as the sclerotized ventral 

 side of the thorax, case-bearing, small size and feeding on algae. However, 

 162 the structure of the case is completely different; the case of Hydroptilidae is 

 built in the 5th stage;* it consists of secretion, rarely has a primitive 

 outer layer, and resembles the pupal cocoons of Glossosomatidae more 

 than their heavy portable cases.** The 1st- to 4th- stage larvae have no case. 

 A primitive character of the larvae is also their primary chaetotaxy, 

 especially (in the lst-stage larva) the long abdominal setae, the presence of 

 dorsal sclerites on the abdominal segments, the absence of a portable case 

 in the first 4 stages; the case of most forms is without any lining. 



The primitive characters of the Philopotamidae are well marked; the 

 larvae live in immovable tunnel-shaped cases; they are microphagous, 

 their legs are short and of similar length and form; the abdominal segments 

 are divided by deep constrictions; their cross section is round or slightly 

 flattened; the abdomen is vermiform and long. As in the higher Annuli- 

 palpia, the sclerite of segment 9 is absent. The labrum is highly specialized, 

 retractile and movable; its greater part is membranous and it bears a 

 small medial sclerite at the base. Pupation takes place in the same cavelike 

 cases as in Rhyacophila; however, the cases are less well constructed 

 and are less solid; the pupa is situated in a loose cocoon inside the case. 



The Stenopsychidae are closely related to the Philopotamidae; these 

 2 families were for a long time considered as 1 family. The Stenopsychidae 

 differ from the Philopotamidae in size; the larvae are among the largest 

 of Trichoptera; they live in tunnel- shaped tubes on pebbles in turbulent 

 streams; they are microphagous; their body structure is simple as in the 

 Philopotamidae; the abdomen tapers posteriorly; segment 9 bears a simple 

 claw as in all Philopotamidae. Microscopic food is collected from the walls 

 of the tube by the long, narrow head and the characteristic labrum, which is 

 broad, short and has a dense brush of thin hairs at the anterior margin. The 

 pupa is situated in a cavelike case which is built of small stones or large 

 sand grains; the cocoon is loose. 



We omit the Ecnominae in discussing the family Psychomyiidae, because 

 this subfamily was separated as a family (Lepneva, 1956:16—26; Marlier, 

 1958:314). The larvae of Psychomyiidae live in tunnel-shaped tubes in slow 

 streams; this was probably the mode of life of the order's ancestors. The 

 body structure is simple; the forelegs are longer than the mid- and hind 

 legs; the chaetotaxy of head, mesothorax, metathorax and legs is primary. 



" In distinction to Siltala (1907:390-391), who thought that the larvae of Stactobia build their case at the 

 end of the 4th stage, Danecker, (1961:226), who studied the life history of Stactobia eatoniella and 

 S. f use ic or n is, confirms the fact that both species begin the building of the case only in the 5th stage; 

 S. fuscicornis begins immediately after molting, and S. eatoniella 4 days later. 

 ** Betten (1934:10) connected the membranous case of Hydroptilidae genetically with the pupal cocoon of 

 Glossosomatidae and Rhyacophilidae; Nielsen (1948:188) does not recognize this homology. 



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