168 



Jewett: Plecoptera 



Fig. 6:25. a, Megaleuctra kincaidi; b, M. spectabilis; c,d, 

 Pe/omyi'o collaris; a,c, lateral view of male terminalia; b, lateral 

 view and d, ventral view of female terminalia (o, Frison 1942o; 

 b, Neove, 1934; c,d, Frison, 1936). 



Subfamily LEUCTRINAE 



Members of this subfamily are distributed throughout 

 the Holarctic region, South Africa, and Tierra del 

 Fuego. The North American fauna includes about 

 twenty-eight species in three genera. The genus 

 Megaleuctra Neave 1934 (figs. Q:7m; 6:25a, b) has 

 been rarely collected; no California specimens have 

 been recorded, but. two species occur in Oregon. 

 Perlomyia Banks 1926 is confined to western North 

 America, and P. collaris Banks 1906 (synonyms: 

 P. solitaria and P. sobrina Frison 1936) (fig. 6:25c, d) 

 is known to occur in California. Adults of the pre- 

 ceding two genera may be placed by employing the 

 key on pages 157 to 160. The genus Leuctra contains 

 five recognized subgenera, three of which occur in 

 California. The California species are keyed below. 



Key to Adults of North American Subgenera and 

 California Species of Leuctra 5 



1. No ventral lobe on the 9th sternite of male (fig. 6:266); 

 abdomen of female not sclerotized dorsally and only in 

 very small patches on the sides (fig. 6:26d); Alaska and 

 Alberta to California. . .(synonym: glabra Claassen 1923) 

 (subgenus Despaxia Ricker 1943) augusta Banks 1907 



— Ventral lobe present on the male 9th sternite; abdomen 

 of female normally sclerotized on the sides and below 

 (except in L. claasseni which occurs in midwestern 

 United States) 2 



2. In the male, backward-pointing processes nearly always 

 present on one or more of tergites 6 to 8; female sub- 

 genital plate deeply cleft medially; cerci always simple; 

 eastern North America .... Leuctra, s.s. Stephens 1835 



— In the male, backward-pointing processes absent from 

 _the tergites; .female subgenital plate not simply cleft 



except usually in Paraleuctra 3 



3. Ninth and 10th tergites of male with a broad depressed 

 membranous area dorsally; cerci with a sclerotized 

 rounded hump near the apex on the inner and upper 

 side; dorsum of female abdomen completely membranous; 

 West Virginia; Ohio; Indiana; Illinois; Missouri, and 

 Oklahoma (sub- 

 genus Zealeuctra Ricker 1952) claasseni Frison 1929 



— Ninth tergite of male fully sclerotized; cerci not as 

 above though sometimes with 2 or more heavily sclero- 

 tized prongs; female with a median dorsal sclerotized 

 stripe on the abdomen on either side of which is a 

 membranous area 4 



4. Cerci of male heavily sclerotized with terminal and 

 lateral pointed projections; body color usually black; 

 subgenital plate of female with lateral projections 

 and a median notch 



(subgenus Paraleuctra Hanson 1941) 5 



— Cerci of male large, membranous or weakly sclerotized, 

 without sharp angles (fig. 6:26a); subgenital plate of 

 female with a median projection below and anterior to 

 the 2 lateral projections (fig. 6:27c); body color brown 

 with a whitish stripe along the costal space of the fore 

 wing; British Columbia to California (sub- 

 genus Moselia Ricker 1943) infuscata Claassen 1923 



5. Titillator of the male with a large membranous bulb at 

 the tip; the longer prong of the bifurcate cercus is 





•Adapted from Ricker (1943, 1952). 



Fig. 6:26. Terminalia of Leuctra. o, infuscata, dorsal view of 

 male; b, augusta, lateral view of male; c, forc/pafa, lateral view 

 of male; of, ougusto, ventral view of female; e, sora, lateral view 

 of male; f, occidentalis, lateral view of mole, (a,b,e,f, Needham 

 and Claassen, 1925; c, Frison, 1937; d, Ricker, 1943) 



