172 



Jewett: Plecoptera 



a short tooth near the base of the bifurcation (fig. 



6:33c); California 



calif ornica (Needham and Claassen) 1925 



— Supra-anal process not broadly bifurcate 8 



8. Lobes of the 10th tergite large and markedly excavated 

 laterally (fig. 6:34a"); wings moderately fumose but with 

 an irregular clear band across the fore wing in the area 

 of the cord; California raynoria (Claassen) 1937 



— Lobes of the 10th tergite smaller and not markedly 

 excavated laterally; wings clear or slightly fumose with 

 a clear band across the fore wing in the area of the 

 cord 9 



9. Lobes of the 10th tergite separated at their base by a 

 distance no more than their length (fig. 6:34a); wings 

 clear; British Columbia to California; Utah and Colorado 

 (synonyms: banksii N. & Clsn. 1925, pallidura Clsn. 

 1936, and kincaidi Hoppe 1938) pallida (Banks) 1902 



— Lobes of the 10th tergite separated at their base by a 

 distance 2 or 3 times their length (fig. 6:346); wings 

 clear or slightly fumose with a clear band in the area 

 of the cord; British Columbia and Alberta to California 

 and Colorado pacifica (Banks) 1900 



Fig. 6:35. a,d, Pteronarcys californica; b,e, Pteronarcys 

 pr/nceps; c,g, Pteronarcella badia; f,h, Pteronarcella regularis; 

 a,b, lateral view of male terminalia; c,f, dorsal view of male 

 terminalia; d,e,g,h, ventral view of female terminalia (Needham 

 and Claassen, 1925). 



— Ninth sternite without a keel; processes of the 10th 

 tergite rounded if present; vein Cu, in the fore wing 

 with usually only 2 branches 



(subgenus Taenionema Banks 1905). ... 4 



4. Tenth abdominal tergite without 2 raised, rearward- 

 pointing appendages 5 



— Tenth abdominal tergite with 2 raised rearward-pointing 

 appendages 7 



5. Lobes at base of cerci large, rounded, and directed 

 forward (fig. 6:34c); Alpine Creek, Tahoe, California 

 vanduzeei Claassen 1937 



— Lobes at base of cerci spinelike and directed backward 

 6 



6. Supra-anal process gradually tapering to a point; wings 

 usually heavily infuscated (fig. 6:336); British Columbia 

 and Alberta to California and Colorado 



nigripennis (Banks) 1918 



— Supra-anal process enlarged toward tip which is broadly 

 rounded; wings lightly infuscated with a clear band 

 across the cord and the tip (fig. 6:33a) southern Cali- 

 fornia grinnelli (Banks) 1918 



7. Supra-anal process broadly bifurcate in side view with 



Family PTERONARCIDAE 



This is primarily an American family and is otherwise 

 known to occur only in Siberia and Sakhalin. The 

 genus Pteronarcella contains two species which are 

 confined to western North America. P. regularis 

 (Hagen) 1874 (fig. 6:35/,A) is definitely known to 

 occur in California, and P. badia (Hagen) 1874 (fig. 

 6:35c,<?) also probably occurs in mountains east of 

 the main Sierra. Pteronarcys contains two subgenera, 

 one of which, Allonarcys, is Appalachian in distribu- 

 tion. Pteronarcys, s. s., is transcontinental in distri- 

 bution and is represented in California by two widely 

 distributed western species. The following key to the 

 family will separate the North American subgenera 

 and the adults and nymphs of the California species. 



Key to North American Genera and Subgenera and 

 California Species of P e teronarc I dae ° 



1. Abdominal gills, reduced in the adult, on first 3 seg- 

 ments; adults and mature nymphs less than 30 mm. in 

 length Pteronarcella Banks (1900) 2 



— Abdominal gills on first 2 segments only; adult and 

 mature nymph usually at least 35 mm. in length 



Pteronarcys Newman (1838) 3 



2. Nymphs with filaments of gill tufts less than twice as 

 long as the basal conical process of gill tufts; adult 

 male with the recurved, scoop-shaped appendage on the 

 dorsum of the 9th abdominal segment acutely pointed 

 at the apex and its side margins straight (fig. 6:35/); 

 adult female with hind margin of the subgenital plate 

 acutely notched (fig. 6:35A); Alaska to California 



regularis (Hagen) 1873 



— Nymphs with filaments of gill tufts at least twice as 

 long as the bases of the gill tufts; adult male with the 

 appendage on the dorsum of the 9th abdominal segment 

 broadly rounded at the apex and its side margins 

 sinuous (fig. 6:35c); adult female with the hind margin 

 of the subgenital plate rounded, truncate, somewhat 

 trilobate, but never acutely notched (fig. 6:35c); Alberta 

 to Nevada and Colorado badia (Hagen) 1873 



3. Nymph with paired lateral .projection on the abdomen; 



'Adapted from Needham and Claassen (1925) and Claassen 

 (1931). 



