The large branch 9 consists of 10 groups distributed in eastern Asia, 

 partly in southern Asia, and in North America; there are no European 

 species in branch 9. The larvae of the species of branch 9 are little known; 

 only the larvae of some species of 3 groups of the branch are known. In the 

 group "nigrocephala," the larvae of the Ussuri species R h. lata and 

 144 probably also Rh. manuleata and of the Japanese species Rh. nigro- 

 cephala belong to the group Hyporhyacophila; the larvae of Rh.re- 

 t r a c t a may be placed in group Prosrhyacophila and the larvae of 

 Rh. lieftincki in the group Mesorhyacophila Lepn. 



In addition to Rh. brevicephala and R h. s h i k ot s u e n s i s , the 

 larvae of which belong to the group Hy p o r hy a c o ph il a, and the 49 species 

 of Rhy acophila not included in the 9 branches, there are also 3 species 

 which, according to the larvae, do not belong to Dohler's groups (which were 

 based on European material); these are R h. i m p a r and Rh. yamana- 

 k e n s i s, the larvae of which have a sword- shaped process of the anal legs, 

 but which either lack thoracic and abdominal gills (Rh. impar) or lack 

 abdominal gills but have single thoracic gills (R h. y a m a n a k e n s i s); as 

 an addition to Dohler's scheme, the author separates these species as the 

 group Mesorhyacophila Lepn. (see p. 236 and Lepneva, 1963:62— 63); 

 to the same group belongs the species Rh. lieftincki of the group 

 "naviculata" from Java (branch 9); the larva of this species was described 

 by Ulmer (1957:138-139, Plate 11, Figures 22-26); like the larva of 

 Rh. yamanakensis,it has only thoracic finger-shaped gills and a sword - 

 shaped process of the anal legs similar to that of the larvae of Rh. impar; 

 to the group Mesorhyacophila belong the American species Rh.fus- 

 cu la (group "fuscula" of branch 4), Rh. at rat a and Rh. melita of 

 group "sibirica 1 ' (branch 7); the larvae of this species have no gills but 

 have a sword-shaped process of sclerite "b" of the anal legs; this process 

 has a slightly irregular form. Recent descriptions and drawings of larvae 

 of the American species placed by us in the groups Hyporhyacophila, 

 Mesorhyacophila and Pa 1 e o r hy a c o ph i 1 a were given by Flint (l 962). 



The larvae of Rh. hokkaidensis (not included by Ross in the groups) 

 and of Rh. acropedes of branch 3 were separated as the group 

 Pale or hy a c ophil a Lepn. (Lepneva, 1963:68); these larvae resemble 

 on the whole the type Hyporhyacophila; they have a simple sclerite "b" 

 of the anal legs without a sword-shaped process; however, like the higher spe- 

 cies of Rhy ac ophil a, they have branched pleural and dorsal abdominal gills. 



Mesorhyacophila and Pa 1 e o r hy a c op hi 1 a are intermediate 

 between species with primitive larvae of the type Hyporhyacophila 

 and Prosrhyacophila and the species of higher groups of the genus, 

 which have complex gills and anal legs with a large sword- shaped process 

 (group "vulgaris" of branch 4). 



Branch 4 consists of 2 small North American groups, including the group 

 "f us cula, " which includes Rh. f u s c ula placed in the group Mesorhya- 

 cophila; branch 4 also contains the large group "vulgaris" (45 species), 

 which consists of only European and Caucasian species. The group 

 "vulgaris" contains species the larvae of which have similar complex anal 

 legs with a large sword-shaped lateral process of sclerite "b" and different, 

 complex thoracic and abdominal gills. Dohler distributes these larvae in 

 several groups. To the group Pararhyacophila Dohler (the larvae of 

 which have abdominal gills which form a tuft of 4 short finger-shaped 

 filaments) belong Rh. intermedia (Central Europe), Rh. forcipulata 

 (Caucasus) and Rh. b a c u r i a n i c a (Caucasus, Lepneva, 1961:655— 656); 



135 



