SCENOPINIDAE OF THE WORLD 223 



Key to Species of Pseudatrichia (males) 



1. Wing brown fumose 2 



Wing hyaline 5 



2. Halter knob with dorsal surface brown, red-brown, or black 3 



Halter knob with base red-brown, remainder white 



P. parvipennis, new species 



3. Halter knob with dorsal surface brown or red-brown 4 



Halter knob black with tip white (Brazil) . . P. punctulata D. E. Hardy 



4. Halter knob all red-brown (Costa Rica) ... P. longiventris, new species 

 Halter knob with dorsal surface brown, ventral surface white 



P. toupeta, new species 



5. Halter knob white 6 



Halter knob with at least the base brown 7 



6. Antenna red-brown P, morlani, new species 



Antenna orange P. melanderi, new species 



7. Halter knob with base red-brown, remainder white 8 



Halter knob with color at least along the dorsal rib 11 



8. Antenna red-brown 9 



Antenna black-brown or orange 10 



9. Ventral margin of 9th tergum short, 9th sternum with a thin comb of hairs 



P. atombomba, new species 

 Aedeagal structures very large, 9th sternum with a thick comb of hairs 



P. cajoni, new species 



10. Antenna black-brown P. unicolor Coquillett 



Antenna orange-brown P. gracilipennis, new species 



11. Dorsal rib of halter knob red-brown bleeding into white 12 



Dorsal rib of halter knob brown with no bleeding or dorsal surface brown . 13 



12. Vein R4 ending well beyond end of cell R5 ... P. barnesi, new species 

 Vein R4 ending equal to end of cell R5 P. truncata, new species 



13. Doral surface of halter knob red-brown, brown or black-brown 14 



Only dorsal rib of halter kiioVj red-brown, remainder white 



P. bupennis, new species 



14. Dorsal surface of halter knob brown or black-brown 15 



Dorsal surface of halter knob red-brown .... P. cockerelli, new species 



15. Ventral surface of halter knob white P. punctulata D. E. Hardy 



\'entral surface of halter knob black-brown, except a small white spot 



P. peromysci, new species 



Key to Species of Pseudatrichia (females) 



1. Wing smoky brown 2 



Wing hyaline 6 



2. Halter knob partly white 3 



Halter knob brown or red-brown 4 



3. Halter knob with base red-brown remainder white . . P. jamesi, new species 

 Halter knob with base and dorsal rib red-brown, bleeding into white 



P. cloudcrofti, new species 



4. Antenna red-brown 5 



Antenna black, short, 7th abdominal segment sharply constricted at base 



(Brazil) P. punctulata I). E. Hardy 



5. Abdomen with 8th segment long and narrow (Costa Rica) 



P. longiventris, new species 



