14;49rf) Dolichopus Latreille 



— Posterior basitarsus without bristles above (fig. 14:49A) 



, 2 



2. First antennal segment hairy above 3 



— First antennal segment bare above 5 



3. Arista apical 4 



— Arista dorsal (fig. 14:49^, h)\ eyes very hairy and verti- 

 cally elongated; face narrow in middle, broad below, 

 and reaching the lower corners of the eyes 



Tachyttechus Loew 



4. Third antennal segment subtriangular or triangular; 

 wing broad at base; body with silvery white dust 



Argyra Mac quart 



— Third antennal segment either furcate or with a strong 

 angular projection basally; mesonotal bristles reduced; 

 face broad, palpi large Hypocharassus Mik 



5. Third antennal segment long and pointed at least in 

 the male with an apical arista; male genitalia long 

 and free 6 



— Third antennal segment shorter, never pointed at tip 

 and arista usually dorsal or subapical; male genitalia 

 short and imbedded 7 



6. Hind cross vein distant from margin of wing; palpi 

 appressed; genitalia of male pedunculated 



Systenus Loew 



— Hind cross vein situated close to wing margin; palpi 

 disengaged and hanging downward; male genitalia not 

 pedunculated Aphrosylus Walker 



7. Hind cross vein equal to or longer than last section of 

 5th vein (fig. 14:49A); fore femur and tibia usually with 

 short, stout ventral spines 8 



— Hind cross vein much shorter than last section of 5th 

 vein; midleg of male usually greatly modified and 

 distorted Campsicnemus Walker 



8. Mouth parts with outer lobe of labella greatly enlarged 

 in the form of a movable sclerotized mandiblelike 

 structure Melanderia Aldrich 



. — Outer lobe of labella not modified. .Hydrophorus Meigen 



California Species of Aquatic Dolichopodidae 



Subfamily DOLICHOPODINAE 



Genus Dolichopus Latreille 



(Fig. 14:4Hs,jO 



This genus includes most of the commoner, large, 

 strong-bodied, bristly members of the family. Little 

 is known of their breeding habits, although Johannsen 

 (1935) reported that Needham took an adult of D. 

 scoparius Loew in a tent trap over a brook in the 

 Adirondacks, and Peterson (1951) figured the larva 

 of D. ramifer Loew reared from decayed vegetation. 

 Nielsen, et al. (1954) figured the larva of D. plumipes 

 Scopoli from soil in a variety of wet and dry situations 

 in Iceland. Our knowledge of the biology, distribution, 

 and taxonomy of the genus is admirably presented in 

 the monograph by Van Duzee, Cole, and Aldrich 

 (1921). The following key to the California males is 

 adapted from a later revision of their keys by Van 

 Duzee and Curran (1934). The females are not nearly 

 so well known and are more difficult to separate. 



Key to Males of the California Species of Dolichopus 



1. At least 1 pair of femora mostly black or the femora 



451 

 Wirth and Stone: Diptera 



with blackish stripes below -' 



— Femora yellow; at most the tip "I the po terioi 

 black I 



'J. Lower orbital cilia pale 8 



— Lower orbital cilia whollj black; rarelj a few pale 

 hairs between the blm k one B 



3. Mu Idle tibia black II 



— Middle tibia yellow 'J.'i 



4. Lower orbital cilia pale . r > 



— Lower orbital cilia black, at most 1 or 2 pale ones 

 below; northern and central California 



bruesi Van Duzee 1921 



5. Squamal cilia black, the short hairs often yelh. 

 6 



— Squamal cilia pale 25 



6. Posterior tibia yellowish, at most slightly brownish at 

 the apex 7 



— Posterior tibia with black apex 27 



7. Posterior tarsus wholly black 37 



— Posterior tarsus with the 1st segment at least 1/2 

 yellow 43 



8. Anterior tibia black or blackish 9 



— Anterior tibia yellow or yellowish; Humboldt County 



andersoni Curran 1924 



9. Last segment of front tarsus compressed 10 



— Front tarsus plain 12 



10. Fifth segment of front tarsus somewhat obcordate, 2nd 

 and 3rd usually yellowish; Shasta and Mariposa counties 

 manicula Van Duzee 1921 



— Front tarsus wholly black, the 5th segment not notched 

 at tip 11 



11. First antennal segment yellow below; 5th segment of 

 front tarsus cut off rather straight at tip; Sierra Nevada 

 acricola Van Duzee 1921 



— Antenna wholly black; 5th segment of front tarsus ex- 

 tended a little at upper corner; northern and central 

 California corax Osten Sacken 1S77 



12. Genital lamellae wholly black, or brown with a black 

 border; Mono and San Benito counties 



barbaricus Van Duzee 1921 



— Genital lamellae whitish or yellowish with a black 

 border 13 



13. Posterior femur ciliated below; central and southern 

 California paluster Melander and Brues 1900 



— Posterior femur without cilia below;* Placer County 



monticola Van Duzee 192 1 



14. Cilia of the squamae pale 15 



— Cilia of the squamae black 18 



15. Costa considerably enlarged before the tip of 1st vein; 

 Mariposa and Modoc counties . . viridis Van Duzee 1921 



— Costa not or with a small enlargement at tip of 1st vein 



16 



16. Genital lamellae large, blackish, rather pointed at tip; 

 Mono County nigricauda Van Duzee 1921 



— Genital lamellae whitish with a black border, at most 

 a little brownish 17 



17. All segments of middle tarsus slightly compressed; 

 Inyo County squamosus Van Duzee 1921 



— Middle tarsus plain, normal; Tulare County 



formosus Van Duzee 1921 (part) 



18. Hind femur ciliated on lower surface 19 



— Hind femur without cilia below 20 



19. Middle and hind femora each with 2 preapical bristles, 

 placed one before the other; Humboldt County 



aedequatus Van Duzee 1921 



— Middle and hind femora each with 1 preapical bristle; 

 central and southern California 



myosota Osten Sacken 1887 (part) 



20. First segment of posterior tarsus with 10-12 large 

 bristles; Sierra Nevada., multisetosus Van Duzee 1921 



— First segment of posterior tarsus with 2-6 large bristles 



21 



