7 (2). Larva light; head and pronotum yellowish; dorsal and lateral stripes 



slightly dark, dots dark; space between dorsal and lateral stripes 

 almost as yellow as the anterior part of the head; gill filaments 

 thin and long 3. Rh. cupressorum Mart. (p. 227) 



8 (l). Posterior margin of each half of the pronotum with a broad, distinct, 



brown, complete or incomplete transverse stripe. 



9 (14). Dorsal stripes of head short, broad, almost completely fused with 



the lateral stripes; posterior part of the pronotum with a large, 

 dark, broad spot. 



10 (13). Dorsal stripes on head widely separated in the middle. 



11 (12). Posterior margin of sclerite of segment 9 light in the middle, with 



narrow dark stripes laterally 4. Rh. nubila Zett. (p. 231) 



12 (ll). Posterior margin of segment 9 with a continuous dark brown 



margin; no interruption in the middle of the posterior margin . . 

 5. Rh. subnubila Mart. (p. 233) 



13 (l0). Dorsal stripes of head situated close together in the middle; a 



narrow light stripe along the coronal suture 



6. Rh. dorsalis Curt. (p. 234) 



14 (9). Space between dorsal and lateral stripes distinct, light or hardly 



noticeable; broad dark spot in posterior part of pronotum absent; 

 rows of dots in posterior part of pronotum on a light or slightly 

 dark background 7. Rh. vulgaris Pict. (p. 235) 



1. Rhyacophila septentrionis McLachlan 



Klapalek, 1893:126-128.- Struck, 1903:79, Plate IV, Figure 4.- Ulmer, 

 1903:127-128, Figures 11, 22, 36, 46, 72, 83, 108; 1909:220, Figure 344, b. - 

 Siltala, 1905:146-148, Figure 39.- Lestage, 1921:415-417, 419, Figure 134, b, 

 j, k. - Nielsen, 1942:337-358, Figures 10-22.- Hickin, 1954:59—61.- 

 Mackereth, 1954:150—151, Figures 1, s; 3, s. 



Full-grown larva (5th stage), Length at end of 5th stage 23.0— 23.4 mm. 

 Sclerites light brown or reddish yellow; pattern brown or dark brown. 

 Head (Figures 181, 182) oblong, dorsoventrally compressed; eyes situated 

 dorsolaterally, near the anterior margin; antennae situated anterior to eyes, 

 near the dorsal articulation of the mandibles. A dark heart-shaped spot 

 in the posterior part of the frontoclypeus which does not reach the angle of 

 the frontal sutures and bears light dots. Gula small, triangular. Setae at 

 anterior margin of frontoclypeus thin and light; lateral seta situated lateral 

 to the frontal suture; intermediate seta smaller than lateral or median seta; 

 213 median and especially anterior frontal seta small; posterior seta markedly 

 longer. Seta 9 longer than seta 7; seta 8 slightly displaced from the anterior 

 margin of the head; setae 11 and 10 very small and light; setae 14, 15 and 12 

 long and dark and of about the same length; seta 12 slightly thicker than the 

 others; seta 16 shorter than setae 12, 14 and 15; seta 17 situated near the 

 angle of the frontal sutures, rudimentary; ventral seta 18 small, strong, 

 situated at about the middle of the gular suture. 



Labrum (Figure 183) uniformly rounded anteriorly and laterally, with a 

 broad margin covered with small setae; dorsal sclerite thin and yellowish, 

 with a broad rounded median notch; seta 1 light, curved; the membrane in 

 the median notch with the small seta 4; setae 2 and 5 longer and stronger 



5724 220 



