FAMILY DROSOPHILID.E THE SMALL FRUIT FLIES 327 



KEY TO GENERA 



1. Discal and second basal cells united (18) 2 



Discal and second basal cells separated (17) 14 



2. Auxiliary vein ending in the first vein near its base 4 



Auxiliary vein entire or nearly so 3 



3. Arista plumose; prescutellar acrosticals strong; costa pectinate (23, 



24 ) Curtonotum Macquart 



Arista pubescent; prescutellar acrosticals absent. . .Aulacigaster Macquart 



4. Arista pubescent or bare with one long ray above 5 



Arista plumose 6 



5. Arista with one long ray above (1, 13) Cladochaeta Coquillett 



Arista pubescent Pseudiastata Coquillett 



6. Proboscis longer than head-height; head broader than the thorax (6, 



9, 18) Zygothrica Wiedemann 



Proboscis shorter than the head; head rarely broader than the thorax. 7 



7. Lower reclinate frontal bristle as far from the proclinate as from the 



upper reclinate 8 



Lower reclinate frontal situated nearer to the proclinate than to the 

 upper reclinate 10 



8. Prescutellar acrosticals strong; face not protuberant 9 



Prescutellar acrosticals weak or absent; face produced. 



Pararhinoleucophenga Duda 



9. Costa ending at the third vein (3, 15) Leucophenga Mik 



Costa extending to the fourth vein (2, 12) Rhinoleucophenga Hendel 



10. Lower reclinate frontal situated in front of the proclinate (5, 27). 



Chymomyza Czerny 

 Lower reclinate situated behind the proclinate 11 



11. One large pair of dorsocentrals; mesonotum and scutellum usually 



convex; a single bristle at the second costal break (11, 19). 



Mycodrosophila Oldenberg 

 Usually two pairs of dorsocentrals 12 



12. Acrostical hairs moderately long and not very numerous, never in more 



than four rows anteriorly (10, 25) Scaptomyza Hardy 



Acrostical hairs short and appressed, always in six or more rows 

 anteriorly 13 



13. Prescutellars long and strong Clastopteromyia Malloch & McAtee 



Prescutellar acrosticals quite weak or absent (4, 16) . . . .Drosophila Fallen 



14. Arista pubescent or bare 17 



Arista plumose 15 



15. Propleural bristle present but weak (8, 17) Diastata Meigen 



Propleural bristle absent 16 



16. Face fiat on upper half, prominent in the middle (7, 26). 



Planinasus Cresson 

 Face concave, the oral margin the most prominent (14, 21). 



Stegana Meigen 



17. Antennae extending to the oral margin, the third segment twice as long 



as wide Tryptochaeta Rondani 



Antennae not reaching the oral margin (20, 22) . .Sinophthalmus Coquillett 



