low upper margin of mesopleuron; legs black, knees 
yellow; squama yellow, fringe black; wing length 
from 2.5 mm in male to 3.1 mm in female; 2d costal 
section equal to or slightly longer than 4th, 
discal cell minute; male genitalia with aedeagus 
(figs. 1065, 1066) having distiphallus elongate, 
well-developed paired triangular sclerite below 
its base. 
Host/Early Stages. Achillea , possibly other 
genera of Asteraceae. Larva feeding and pupating 
in stem. 
Distribution. California; new record: Colorado, 
Teller Co., Cameron Pass, 2 m. , 11. VIII. 55 
(G. F. Knowlton, CNC) ; widespread in Alaska, 
northern Canada, Finland, Norway, Sweden north of 
Arctic Circle. 
References. Spencer, 1969a: 217; 1981: 359. 
7 (5). Male genitalia with distiphallus elongate (fig. 
1067)- N. manni Spencer, n. sp. 
Synopsis. Frons 1.5 times width of eye, orbital 
setulae numerous in area of lower ori; gena ex- 
tended at rear, almost 0.5 height of eye; wing 
length in male 2.75 mm; male genitalia with 
distiphallus elongate (fig. 1067) having narrow 
process below (contrast N. plumea , fig. 1065); 
sperm pump rounded (fig. 1068), strongly pig- 
mented . 
Host/Early Stages. Unknown. 
Distribution. Colorado. 
Reference. Part 2, p. 308. 
Male genitalia with distiphallus not elongate (see 
figs. 1069, 1071) 8 
8(7). Male genitalia with distiphallus conspicuously 
swollen basally in side view (fig. 1069) 
- N. schusteri Spencer 
Synopsis. On external characters agreeing closely 
with N. plumea , apart from less pubescent 3d an- 
tennal segment; male genitalia with aedeagus 
having connecting tubule between base and apex of 
distiphallus short, with characteristic curvature 
(fig. 1069), in ventral view distiphallus angular 
(fig. 1070). 
Host/Early Stages. Unknown. 
Distribution. California (San Bernardino Mts.). 
Reference. Spencer, 1981: 361. 
Male genitalia with distiphallus only slightly 
swollen basally in side view (see figs. 1071 
1074) L 9 
9 (8). 2d costal section about 1.6 times length of 4th 
7 N. nugax Spencer 
Synopsis. On external characters agreeing closely 
with JJ. plumea but 3d antennal segment appearing 
bare; wing length 2.3— 3.3 mm; male genitalia with 
aedeagus as in figures 1071, 1072, right basal 
sclerite with distinctive angular bend at mid- 
point; sperm pump small (fig. 1073). 
170 
