1944] New Neotropical Phoridce 161 
This species differs from most of the Neotropical species of 
the subgenus Aphiochaeta by the presence of four scutellar bris- 
tles in combination with a large bristle on the mesopleura. It 
resembles M. luteicauda Borgm. and M. pteryacantha Borgm. 
in having a bristle at the base of the third vein, but differs by 
the black palpi, entirely black abdomen and narrower front. 
From M. pilipleura Borgm. it differs in color, size and frontal 
chaetotaxy. From M. angustijurcate it differs particularly in 
wing venation and also by the black antennae and palpi. In 
general habitus M. asthenichceta resembles M. minor Zett. al- 
though structurally very different. 
