Fly with unusual pattern on wings

Fly with unusual pattern on wings

Observation - Fly with unusual pattern on wings. Description: Medium sized fly about 12mm long with very noticeable wings because of the dark curvy pattern standing out against the transparency of them. Shiny red-brown abdomen and thorax. Black hairs on thorax and a yellow bead-like lump sticking out at the back.

Medium sized fly about 12mm long with very noticeable wings because of the dark curvy pattern standing out against the transparency of them. Shiny red-brown abdomen and thorax. Black hairs on thorax and a yellow bead-like lump sticking out at the back. A black lump sticking out of the back of the abdomen. Big pale green eyes.