This is a really interesting taxon group (genus?) where the males have very Sarcophaga-like genitalia – quite large, orange and hooked under the abdomen. They also seem to have a tuft of yellow hairs, like a Sturmia-spot, on the ventral side of tergite 5.
EDIT (Monty Wood, 26/9/2010): This is a group of quite unusual Masiphya sp., with a very small distance between the vibrissae and the mouth edge. Normal Masiphya spp. have quite a protruding mouth edge and the vibrissae are raised above the mouth edge. The Masiphya are parasitoids of mantids.