Chaetona sp. (French Guiana)
This is an interesting tachinid with a hairy (not plumose) arista, shaded wing, strong subvibrissal bristles, bristled prosternum etc. It keys to Chaetona but this genus usually has a plumose arista … this one is definitely hairy but not what I should call “plumose”, as such.
EDIT (17/10/2010): Confirmed by Monty Wood from these photographs.