Pipizella

Note that the eyes of male P. viduata are touching over a shorter distance than those of P.virens.
Of the 2 species, P. viduata has shorter hairs on the hind tibia, shorter antenna 3rd segment,
and the females' abdomen is more compact.

Pipizella viduata:

Males:

Females:

Pipizella virens:

Male:

Females: