What insect is this? Is it harmful in any way?

Asked January 19, 2016, 1:01 AM EST

An insect has appeared in our house recently, a month or so. It appears to me to be a type of fly. When sitting still it appears to have a triangular configuration and the distance from outer wing margin to the other is about 1/4". It is mostly black but the wings appear to be somewhat lacy and oval in shape. I will try to include a photo of the insect. After looking at the enlarged picture on the computer it appears to be more like a moth considering the antennae. Carl Bankes

Washington County Oregon

1 Response

Thank you for attaching the excellent image. Even though the insect resembles a moth, it truly is a fly. To be more specific, it’s a drain fly. See “Moth or Drain Flies” at http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74167.html

Drain flies breed in drains and other moist environments with decaying organic matter. They don’t damage people, pets, or structures but, when numerous, are considered a nuisance. The larvae are in the slime layer than lines drains. One way to manage them is to periodically clean the drain with a bottle brush dedicated to that process. Pouring vinegar or boiling ware down the drain won’t help.