Moth Fly
Sam found this tiny insect in her room on July 27, 2014. It was so very small (only a few millimeters long, including the wings) that I’m surprised that she spotted it at all.
It looks like one of the Moth Flies, family Psychodidae, and more specifically in the subfamily Psychodinae. These have semi-aquatic, scavenging larvae, and are well known for breeding in and around sink drains (particularly if they are partially clogged).
Down in the comments, Gunnar Kvifte says that it is most likely Psychoda alternata, the species that is most likely to be found using human-made habitats. He also says,
“This subgenus can be recognized most easily on the spotted wing vein apices and the fifteen-segmented antenna with the three last segments fused into the shape of a snowman (three successively smaller spheres) . The genus Psychoda is very widespread and abundant, and is easily recognized on the roof-shaped wings, the antennae with the final segments reduced and often fused, and often on being paler and less hairy than most other moth flies.”
In spite of resembling moths, they are in fact true flies (Diptera), with only two wings. They are quite fluffy, and not very strong fliers. Their “flight” is more being blown around semi-randomly by the wind, with a little bit of control once they spot a good place to lay their eggs.
They are sometimes considered household pests, as a single moth fly can lay several hundred eggs in a drain, and their entire life cycle is only on the order of a month, so they can breed fast if the conditions are favorable. The best solution when you spot them is just to wash out the sink and clean the trap in the drain, which will get rid of them right away.
The ones that breed in household drains are harmless, but some of their relatives are little tiny biting flies.
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And here I thought it was a superhero for flies. You know, like Spiderman and Batman?
Mothfly! Able to lick nectar and flutter about porch lights all night!
Sorry, the coffee hasn’t kicked in yet. I promise to do better next time.
Hi,
This most likely is Psychoda (Tinearia) alternata, the most common Psychoda (Tinearia) species in North America and the only one to regularly use human habitats. This subgenus can be recognized most easily on the spotted wing vein apices and the fifteen-segmented antenna with the three last segments fused into the shape of a snowman (three successively smaller spheres) . The genus Psychoda is very widespread and abundant, and is easily recognized on the roof-shaped wings, the antennae with the final segments reduced and often fused, and often on being paler and less hairy than most other moth flies.
Believe I had something like your mothfly in my bathroom sink a couple of times last year. Have since started using a bottle brush to clean my drain. Wish I had looked more closely.
I’ve always liked these flies, but most I have seen are much darker. I remember one/some in the basement bathroom of the engineering building in college. There is also ” in the shower room at my work, that I use when I bike commute.
I’ve always imagined them to be very “friendly” and look for them when I use those bathrooms. When I went back to the same school to drop my son off, I checked and “he” has still there.
A couple times I’ve seen them at home, and decided while I still thought they were friendly, I didn’t want the larva in my drains. I little boiling water did them in.
Thanks, Gunnar!
I’ve added your information into the body of the posting.