Small Flies in Your House - Drain Flies, Fruit Flies, Fungus Gnats, Phorid Flies?

These little flies may all look the same at first glance. Drain flies, fruit flies, and fungus gnats, and phorid flies are different insects though. While they are all tiny flies often swarming around your house, they have different characteristics that require different strategies to get rid of each fly.

The good thing is that there usually aren’t any costly actions to get rid of flies of this nature. Often they can disappear after some careful cleaning or you can try to use some homemade fly traps.

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Identifying Small Flies in Houses

Identifying Small Flies in Houses

Fruit Flies

Also Known As: fruitflies, vinegar flies, Drosophila melanogaster, Sophophora melanogaster, pomace flies, banana flies, sour flies

Color: Yellowish to light brown with red eyes.

Characteristics and Appearance: Rounded heads with large red eyes. Females are slightly larger than males.

Size: 1/8 inch (1-3mm) long, about 1/3 the size of a house fly.

Life Span: Fruit flies often live from 40 to 50 days depending mainly on temperature and food sources.

Commonly Found: As the name states, fruit flies love fruit. They can be found swarming around room temperature fruit on a kitchen counter, insides/near sinks and drains, and around garbage cans. Fruit flies generally seek out decaying matter for food. They also can be found at bars and restaurants that have left bottles of liquor open.

Natural Fruit Fly Repellents

By John Tann from Sydney, Australia (Fruit flies feasting) via Wikimedia Commons

Drain Flies

Also Known As: moth fly, sink flies, filter flies, sewer gnats

Color: Ranging from dark brown or gray to black

Characteristics and Appearance: Bodies are covered in tiny hairs resembling a moth. Wings are leaf-shaped with parallel veins running down them.

Size: 1/8 inch (1-3mm) long, about 1/3 the size of a house fly.

Life Span: Adult drain flies live for about 20 days in which they may reproduce once. Eggs hatch within 48 hours.

Commonly Found: Drain flies are non-biting gnats that grow and live in standing water. They will use areas that have still water for breeding grounds so they can often be found around hidden leaks in plumbing. Drain flies in sinks are often actually fruit flies since the drain flies are more attracted to the still water and not the continuously used water in a sink.

Fungus Gnats

Also Known As: Sciaridae, dark-winged fungus gnats

Color: Dark greyish to black with grey see through wings.

Characteristics and Appearance: Thinner bodies than fruit flies with long lanky legs and antennae. They are weak fliers and can usually be seen quickly walking instead of taking flight.

Size: 1/8 inch (2-8mm) long, about 1/3 the size of a house fly.

Life Span: Adults usually live for 7-10 days and can lay 100s of eggs in that lifespan.

Commonly Found: They are often found around houseplants. The potted soil is a perfect breeding ground for fungus gnats. They are also attracted to light and can be seen flying around light fixtures or windows.

Natural Deterrents: cinnamon

Phorid Flies

Also Known As: scuttle fly, coffin flies, sewer flies

Color: Dark brown to blackish

Characteristics and Appearance: Phorid flies have an apparent humpback shape when viewed from the side. Rather than flying, you’ll notice that they usually quickly run when making an escape.

Size: 1/16 – 1/4 inch (0.4-6mm) long

Life Span: Depending on the temperature and environment, phorid flies can live for 1-2 months.

Commonly Found: Phorid flies are what are considered filth flies which means that they will breed around and feed on decaying matter. They are often found in clogged drains and around rotting food. They are also commonly found around dead animals including mausoleums and churches with crypts.