ONH

Small-headed Fly

Eulonchus tristis

  • 1635
  • 3303
  • 0010
  • 4385
  • 4385cu
  • 4502
  • 4510
  • 8297
  • 1635
    1 - Small-headed Fly mating pair, Eulonchus tristis, on a Salal leaf.

    06/27/2007 Heart O' the Hills Area, Olympic National Park, Washington

  • 3303
    2 - Small-headed Fly mating pair, on a Salmonberry leaf.

    06/27/2007 Heart O' the Hills Area, Olympic National Park, Washington

  • 0010
    3 - Small-headed Fly.

    06/29/2009 Heart O' the Hills Area, Olympic National Park, Washington

  • 4385
    4 - Small-headed Fly mating pair, on a Salmonberry leaf.

    06/27/2007 Heart O' the Hills Area, Olympic National Park, Washington

  • 4385cu
    5 - Small-headed Fly male, closeup showing the golden hairs on the eye.

    06/27/2007 Heart O' the Hills Area, Olympic National Park, Washington

  • 4502
    6 - Small-headed Fly mating pair, on a Salal leaf.

    07/04/2011 Heart O' the Hills Area, Olympic National Park, Washington

  • 4510
    7 - Small-headed Fly mating pair, on a Salal leaf.

    07/04/2011 Heart O' the Hills Area, Olympic National Park, Washington

  • 8297
    8 - Small-headed Fly mating pair, on a Salal leaf.

    06/09/2009 Dungeness National Wildlife Refuge, Washington

Small-headed flies, family Acroceridae, may feed on flowers as adults, or may not feed at all as adults. They lay eggs on leaves and the eggs hatch into tiny, flat larvae that then burrow into a passing spider, later emerging to pupate on the web. These Small-headed flies, Eulonchus tristis, often in mating pairs, appear in June or July. The female is a little over 1 cm in length.

Thanks to Eric Eaton and Dennis Haines at bugguide.net for identification.