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1 . Hydatophylax magnus Marty no v (Stenophylax 

 magnus Martynov), larva nova 



Full-grown larva. =■= Length 28 — 32 mm. Main color of head and thorax 

 yellow; dots distinct, dark, on brown background, forming dense, short rows 

 and groups, resembling variegated pattern of larvae of Stenopsyche. 

 Frontoclypeus (Figure 479) reddish brown at anterior margin, brownish 

 around and between tentorial pits, posteriorly with a narrow, golden brown 

 stripe along frontal sutures; anterior part with an oblique, brown spot with 

 several fine dots lateral to median pit; 2 median spots with fine punctation 

 close together further posteriorly; wedge-shaped pattern in posterior part 

 situated on light yellow background, consisting of large, distinct, dark 

 brown dots. A narrow, reddish brown stripe along posterior part of frontal 

 sutures and near end of coronal suture; anterior area blackish brown from 

 margin to eye; short transverse and oblique rows of dots on dark back- 

 ground along epicranial suture; sides with similar longitudinal and oblique 

 rows and groups of dots. Ventral surface light brownish in anterior half, 

 whitish yellow posteriorly, with large group of large and small dots, in- 

 cluding 3 dark, transverse, median dots. Gula slightly darker, brownish, 

 extending in a fine point into open gular suture (Figure 480). 



Large setae relatively thin. Median and intermediate anterior- margin 

 setae blackish brown, widely separated, the latter closer to lateral than 

 to median seta; middle frontal seta relatively long, posterior frontal seta 

 short, thin. Seta 7 strong, dark; seta 10 small, light, slightly thickened; 

 setae 9 and 14 of about the same length; seta 11 short, thin; seta 13 lighter 

 and smaller; seta 12 brown, moderately long; seta 15 light brown, thin, 

 long; seta 16 situated slightly posteriorly, light yellowish, small, directed 

 inward; seta 17 strong, dark, large, shorter than middle frontal seta. 

 Ventral seta 8 small, strong; seta 18 minute. 



Labrum reddish brown, darker than head; setae 5 and 6 dark brown, 

 other setae light; seta 3 situated further posteriorly, almost at level of 

 setae 5 and 6. 



Mandibles black; right mandible, in addition to middle tooth with 3 small 

 teeth on dorsal blade and an indistinct tooth more basally; ventral blade with 

 one tooth; left mandible with 2 teeth on dorsal and ventral blade, in addition 

 to middle tooth; lateral setae situated basally, small, ventral seta yellowish, 

 almost half as large as dorsal; median brush forming a tuft of large, golden 

 chaetoids; brush on left mandible larger than on right. 



The large larvae described below were collected in 1927 by I.I. Sokolov, P. D. Rezvoi.and A.V. 

 Martynov, and by -I. M. Levanidova in 1949 in the Maritime Territory, in brooks and rivulets of the 

 system of the rivers Suchan (Sitsa River and tributaries) and Ussuri (Khor, Ugodinza, a tributary of the 

 Daubikhe); I. D. Cherskii, A.I. Kurentsov, A.M. D'yakonov, N.N. Filip'ev repeatedly found in the 

 same area males and females of Hydatophylax magnus Mart., the largest species of the tribe 

 Stenophylacini in the Far East. The largest larvae of this genus found there may be considered to be 

 those of H. magnus. Larvae, pupae, and cases have been found in the following rivers and rivulets: 

 1) Sitsa River, a tributary of Suchan, 11 June 1927, one pupa, A. V. Martynov; 2) brooks and rivulets 

 of the Sitsa system near Tigrovaya Station, 11 and 13 June 1927, 6 larvae, 4 pupae, 6 cases, I.I. 

 Sokolov, A. V. Martynov; 3) rivulet Ugodinza, a tributary of the Daubikhe. a source of the Ussuri, 

 2 specimens, I.I. Sokolov, P. D. Rezvoi; 4) Khor River, Pavlenkovskaya [channel], 6 July 1949, 

 6 larvae, I. M. Levanidova. I. M. Levanidova, who has additional specimens of H yd a to ph yl a x , 

 thinks that the larvae found in the canals of the Khor River are those ofH. magnus. 



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