Our insect of the week for February 2, 2026 is the drain fly [also known as bathroom moth midge and bathroom moth fly] (Clogmia albipunctata) [DIPTERA: Psychodidae]. It was described by Samuel Williston in 1893. Yes, I decided to switch to flies for the start of February. This species often appears in homes and I have been contacted multiple times in winter months asking what this insect is.

This species is known worldwide in tropical and temperate regions, including central Illinois. The adults are often seen near sewer drains (such as sinks) and sewage treatment plants. They may also be observed near potted plants. Larvae are usually associated with moist decaying organic matter. Wings of adults are covered with brown to gray setae. Their antennae are often covered in white setae. Adults can be observed year round, but are often more commonly noted in winter months. Perhaps because we spend more time indoors.

Adults live for about 12 days and drink water and flower nectar to survive. They are poor fliers and are often observed on walls near a sink (or in the sink itself). Larvae (maggots) mature from egg to pupae in about 18 days.

They feed exclusively on decaying organic matter. Yes, it is a disgusting way to make a living, but imagine for a moment what our world would be like without maggots processing all this organic matter. Just imagine the smell. If you see these in your home, they are mostly harmless. There is no easy way to eliminate them. Their bodies are very water repellant and neither adults nor larvae can easily be drowned or killed with hot water. The safest way is to have someone professionally clean your drains. This eliminates the organic matter so the insects will go elsewhere.

This specimen was collected, then frozen. It is laying on its side and has not yet been mounted on a point and pin. The left wing is out of focus, but you can clearly see the venation and setae on the right wing. You can also see the antennae with their white setae. Yes, I am experimenting with my camera (which is why I tried this specimen). The body is about 2 mm in length; these are relatively small and resemble tiny moths (even though they are flies).

The specimen in this photograph was collected (and photographed) by Mark DuBois in Tazewell County, Illinois.