Aphiochaeta. 219 



Group IV. 



Scutellum with two bristles. 



Mesopleura bristly with the bristles uniform, all small. 



Costa long. 



1. Costal cilia short 2. 



— Costal cilia long 6. 



2. Halteres black 3. 



— Halteres yellow 5. 



3. Front metatarsi thickened in both sexes crassipes Wood. 



— Front metatarsi not thickened 4. 



4. Supraantennal bristles unequal; wings tinged, 



angle at fork not large; size 1,5 mm arrnata Wood. 



— Supraantennal bristles equal; wings clear, angle 



at fork nearly rectangular ; size 0,5— 0,75 mm .... affinis Wood. 



5. Frons nearly quadratic, strongly shining; 1 dist- 



inctly more than double 2 39. lucifrons Schmitz. 



— Frons a little broader, less shining; 1 not dist- 



inctly more than double 2 40. suhnitida Lundbk. 



6. Halteres black or at all events dark 7. 



— Halteres yellow 34. 



7. Front tarsi in both sexes more or less dilated, 



at all events metatarsus 8. 



— Front tarsi not dilated (in trichorrhoea slightly) 22. 



8. Front tarsi with only metatarsus distinctly 

 dilated; rather small species, 1,3—1,8 mm (except 

 ohscuripennis) 9. 



— Whole front tarsus thickened in male, in female 

 only metatarsus distinctly thickened; larger 



species 1,5—2 mm 15. 



9. Palpi black or brownish 10. 



— Palpi yellow 11. 



10. Larger species, 1,8— 2, 5 mm; male palpi large. 41. ohscuripennis Wood. 



— Smaller species, 1,3— 1,5 mm; male palpi ordinary 42. conjormis Wood. 



11. Costa 0,45—0,47 of the wing-length; legs brown- 

 ish or darker, last joint of front tarsi not dilated; 



anal tube in male dark 12. 



— Costa reaching to or near to the middle; legs 

 yellow, front tarsi with also last joint a little 



dilated; anal tube in male yellow 46. dactylata Lundbk. 



12. Wings colourless or nearly 13. 



— Wings a little yellowish to brownish, veins brown 14. 



13. Frons pitch-coloured ; front metatarsus not broad, 

 but dilated ventrally; hypopygium richly bristly 



(only male known) cothurnata Schmitz. 



— Frons black; front metatarsus dilated in the 



usualway; hypopygium with only small bristles. . 43. suhcar polis Lundbk. 



14. Costal cilia moderately long; hind femora in male 



