Taenionema pacificum

Taenionema pacificum (Banks)

(Figs. 13, 22, 30, 53, 61, 73, 82, 95, 108)

Distribution. Widespread west of the 100 th Meridian (Alberta, Alaska, Arizona, British Columbia, California, Colorado, Idaho, Montana, New Mexico, Oregon, Utah, Washington, Wyoming, Yukon).

Material Examined. Alaska: Chena River near Fairbanks, 4-IV- 1968, Kreizenbeck, 5♂ nymphs, 5♀ larvae; 10-III-1972, E.W. Shallock & W.M. Jinkinson, ♂ reared with exuvium and 1♂ and 4♀ larvae partially emerged with attached exuvia; 3-IV- 1972, E.W. Shallock & W.M. Jinkinson, ♂ reared with exuvium, 2♀ reared with exuvia; 11-IV-1972, E.W. Shallock W.M. Jinkinson, 29♂ larvae, 11♀ larvae, 2♂ reared with exuvia. Montana: Lincoln Co., Kootenai River, 19-III-1970, R.L. Newell, 2♂ larvae. New Mexico: Rio Arriba Co., Rio de las Vallecitos, R. Hassage, 20-III-1986, 4 reared ♂ with exuvia, 2 reared ♀ with exuvia, 1 partially emerged ♀ with exuvium attached.

Characters. Color, pigmentation (Fig. 13), maxillae (Fig. 30), body, leg (Fig. 53) and cercal setation, and sexual dimorphism (Figs. 61, 73, 82) generally typical of genus. Body length ♂ 8.5- 10 mm, ♀ 9-11 mm. Antennal segments ♂ 64-68, ♀ 64-68. Cercal segments ♂ 46-58, ♀ 44-58. Male 9 th sternum (Fig. 95) ovate with posterolateral sides convex and apex narrowly rounded. Female 9 th sternum (Fig. 108) narrower than ♂, triangulate behind greatest width with nearly straight sides, and pointed apex.