446 



Wirth and Stone: Diptera 



3. Body entirely subshining black, the wings smoky; 

 Santa Barbara to Riverside counties, .ater Brennan 1935 



— Body grayish to dull blackish, only the .costal cell 

 sometimes infuscated 4 



4. Costal cell hyaline; palpi with pale hairs; Lassen to 

 San Diego counties, comastes comastes Williston 1885 



— Costal cell infuscated; palpi usually with some black 

 hairs; San Bernardino, Riverside, and San Diego 

 counties comastes willistoni Brennan 1935 



5. Scutellum yellowish 6 



— Scutellum blackish or cinereous 7 



6. Flagellum black; front entirely pollinose when not 

 irregularly worn; Riverside and Imperial counties .... 



parkeri Philip 1941 



— Flagellum mostly yellow; front with an expansive bare 

 area; Fresno and Tulare counties 



albipilosus Brennan 1935 



7. Front very wide, height and basal width subequal; a 

 narrow mesal, bare brown streak about 2/3 its height; 

 cheeks unusually swollen; Riverside County 



colei Philip 1941 



— Front narrower, about 1:2 or 2:5, the bare area more 

 extensive 8 



8. Body predominantly gray; wings subhyaline; midfrontal 

 bare area widely separated from eye margins; Contra 

 Costa and Los Angeles counties. . similis Brennan 1935 



— Body predominantly brownish or darker; wings fumose, 

 bare area almost touching eye margins; Mariposa and 

 Riverside counties hinei Brennan 1935 



9. Wings hyaline with or without infuscated costal cells 

 or isolated clouds; pleural hairs, at least, largely 

 whitish 10 



— Wings smoky, or palpal and pleural hairs black 13 



10. Costal cell fumose, distinctly darker than remainder of 

 wing comastes willistoni Brennan 1935 



— Costal cell completely hyaline 11 



11. Palpi truncated apically, short and stubby; hairs 

 sparse similis Brennan 1935 



— Palpi elongated, more slender; sometimes obscured by 

 long dense pile 12 



12. Size 14 mm. or more; palpal and facial vestiture dense 



colei Philip 



— Size less than 14 mm.; these hairs not especially dense 



comastes comastes Williston 1885 



13. Shining black species ater Brennan 1935 



— Dull black species with pale abdominal incisures 

 hinei Brennan 1935 



Apatolestes rossi Philip 1949 from Lake County is 

 not included in this key. 



Genus Brennania Philip 

 Brennania hera (Osten Sacken) 1877 



San Francisco, 

 San Mateo, Monterey 



Key to the California Species of Pilimas 



1. Front subparallel, not divergent below; antennae, palpi, 

 and legs reddish including their vestiture; San Bernar- 

 dino County beameri Philip 1942 



— Front divergent below (fig. 14:48rf); apical 1/2 of 

 flagellum black; palpi with black hairs; legs fuscous 

 with dark vestiture; Siskiyou to Riverside counties 



calif ornica (Bigot) 1892 



(= Pangonia dives Williston 1887 and Silvius jonesi 

 Cresson 1919) 



Key to the California Species of Stonemyia 



1. Large robust species (15 mm.), black; the mesonotum 

 of female clothed with pale yellow pile; wing dark 

 brown; a patch of pale yellow hair on middle of poster- 

 ior margin of 2nd tergite; Madera County 



(= albomacula Stone 1940) velutina (Bigot) 1892 



Body length usually less than 15 mm.; body yellowish 



with or without black markings 2 



Proboscis long, at least equaling width of head; ab- 

 domen orange with black markings; legs black; Sierra 



County to Mariposa County 



tranquilla fera (Williston) 1887 



Proboscis shorter than width of head; abdomen and legs 



golden yellow 3 



Entire thorax dark, the 1st tergite and terminal tergites 

 and sternites predominantly so; spots on segments 2-4 



variable (male); Madera and Mariposa counties 



ruficornis (Bigot) 1892 



Integument of entire body and legs concolorous yellow- 

 ish (male); Shasta County to Riverside County 



abaureus Philip 1941 



Key to California Species of Silvius 



1. Females; eyes not contiguous 2 



— Males; eyes contiguous 6 



2. Wings immaculate; orange species; Lassen County to 

 Riverside County gigantulus (Loew) 1872 



— Wings maculate; gray species 3 



3. Costal cell hyaline 4 



— Costal cell infuscated 5 



4. Basal callus about 1/2 width of front, broadly separated 

 from eyes; veins of radial sector with subapical spots 

 (fig. 14:48c); Riverside and San Diego counties 



quadrivittatus (Say) 1823 



— Basal callus distinctly more than 1/2 width of front, 

 narrowly separated from eyes; veins of radial sector 

 without subapical spots; Trinity County to San Diego 

 County notatus (Bigot) 1892 



5. Scape robust; flagellum about as long as scape; Hum- 

 boldt County philipi Pechuman 1938 



— Scape slender; flagellum about twice as long as scape 

 sayi Brennan 1935 



6. Wings immaculate; orange species 



gigantulus (Loew) 1872 



— Wings maculate; gray species 7 



7. Abdomen predominantly yellowish; subapical spots on 

 veins of radial sector; not densely haired species; 

 venter of abdomen with 3 rows of spots 



quadrivittatus (Say) 1823 



— Abdomen predominantly dark; no subapical spots on 

 veins of radial sector; thorax and base of abdomen with 

 long white hair; venter of abdomen mostly dark or with 

 a broad dark median band notatus (Bigot) 1892 



Key to California Species of Chrysops 



1. Females; eyes not contiguous 2 



— Males; eyes contiguous 25 



2. Apex of wing beyond crossband hyaline, sometimes 

 just a trace of a cloud confined to cell R, 3 



— Apex of wing beyond crossband distinctly infuscated 

 6 



3. Femora banded in middle with reddish brown; abdomen 

 greenish yellow with black markings; Butte County to 

 Merced County hirsuticallus Philip 1941 



— Femora black; abdomen otherwise 4 



4. Pile of pleura golden yellow or orange; basal tergites 

 laterally orange; Shasta, Plumas, and Sierra counties 

 excitans Walker 1848 



— Pile of pleura whitish to gray; abdomen black with or 

 without grayish pile 5 



5. Base of cell Cu t with a small hyaline spot 



carbonaria Walker 1848 



— Base of cell Cu 2 infuscated; large obscure gray mid- 

 dorsal triangles more likely to be present; Humboldt 

 and El Dorado counties mitis Osten Sacken 1875 



6. Basal callus orange or orange with lateral and upper 

 margins black 7 



— Basal callus entirely black 14 



