(844) 211-7378Book Inspection

What Do Drain Flies Look Like?

September 16, 2023 - Drain Flies

Author - Tom Miche

what do drain flies look like

Drain flies, also known as sewer gnats or moth flies, are small, winged insects that are commonly found in and around drains, sewage systems, and other damp, organic-rich environments. Here is a description of what drain flies look like:

  • Physical Appearance: Drain flies are quite small, typically measuring between 1.5 to 5 millimeters (0.06 to 0.2 inches) in length. They are usually light gray or tan, but some species may appear brown or black. Drain flies have a distinctive moth-like appearance. Their bodies are slender and covered with tiny, dense hairs, giving them a fuzzy or hairy appearance. They have two membranous wings that are covered in scales, similar to those of moths. The wings are held roof-like over their bodies when at rest. Drain flies have long, thread-like antennae that are often longer than their body.

  • Head and Thorax: The head of a drain fly features prominent, large compound eyes. Their thorax, the middle segment of their body, is relatively large compared to their overall size and is where their wings and legs are attached.

  • Legs: Drain flies have six spindly legs that are often held close to their bodies.

  • Behavior and Habitat: Drain flies are primarily found in areas with high moisture content, such as drains, sewers, septic tanks, and other plumbing fixtures. They are particularly attracted to decaying organic matter, sewage, and sludge, where they lay their eggs. Adult drain flies are weak fliers and are most active during the evening and night, often swarming around drains and sinks.

  • Life Cycle: Drain flies undergo a complete metamorphosis, consisting of egg, larval, pupal, and adult stages. Larvae of drain flies are aquatic and feed on organic matter in the moist environments they inhabit. Once mature, they pupate near their breeding sites, and then emerge as adult drain flies.

Drain flies are small, fuzzy insects with a moth-like appearance. They are typically gray or tan and have distinctive, large compound eyes, long antennae, and slender bodies covered in tiny hairs. They are most commonly found in damp, organic-rich environments like drains and sewage systems, where they lay their eggs and develop through a complete metamorphic life cycle. Understanding their appearance and habits can be helpful in identifying and managing drain fly infestations.

Drain Fly Size

Drain flies, also known as sewer gnats or moth flies, are relatively small insects. On average, they measure between 1.5 to 5 millimeters (0.06 to 0.2 inches) in length. Their size can vary slightly among individual drain flies, but they are generally within this size range. These tiny dimensions make drain flies easily distinguishable from larger flies like house flies or fruit flies. Despite their small size, they can be a nuisance when they infest damp, organic-rich environments such as drains and sewage systems.

What Do Drain Fly Larvae Look Like

Drain fly larvae, also known as drain worms, are the immature stage of drain flies (moth flies). They have a distinct appearance that sets them apart from adult drain flies. Here is a detailed description of what drain fly larvae look like:

  • Size and Shape: Drain fly larvae are elongated and worm-like in shape. They are typically smaller than adult drain flies, measuring about 4 to 5 millimeters (0.16 to 0.2 inches) in length. Their bodies are cylindrical and somewhat translucent.

  • Color: Drain fly larvae are usually a pale, creamy white or gray color.

  • Segments: They have segmented bodies, with several visible body segments.

  • Head: At one end of their body, drain fly larvae have a dark-colored, distinct head capsule. The head capsule contains their mouthparts, which are adapted for feeding on organic matter.

  • Movement: Drain fly larvae move in a wriggling or looping motion, which can be quite distinctive.

  • Habitat: Drain fly larvae are typically found in moist, organic-rich environments, such as the gelatinous slime that accumulates in drains, sewage systems, or stagnant water containing decaying organic matter. They feed on the organic material in these environments, including bacteria, fungi, algae, and other microorganisms.

  • Role in the Life Cycle: Drain fly larvae are the feeding and growing stage of the drain fly life cycle. They reside in their habitat until they pupate and eventually emerge as adult drain flies.

Drain fly larvae are small, worm-like creatures with pale, segmented bodies and a dark head capsule. They are commonly found in damp, organic-rich locations like drains, where they feed on decomposing organic matter. Understanding their appearance and habitat is essential for identifying and addressing drain fly infestations, as they are often the cause of drain-related issues.

Drain Fly Appearance

Drain flies, also known as sewer gnats or moth flies, are typically light in color. Their coloration can vary slightly among individual flies and species, but they are generally characterized by the following colors:

  • Light Gray: Many drain flies are light gray in color. They may appear as pale gray or even slightly silvery, especially when seen in well-lit areas.

  • Tan: Some drain flies have a tan or beige coloration. This can make them blend in with their surroundings, such as bathroom tiles or drainpipes.

  • Brown: In certain cases, drain flies may appear brown, although this is less common than the gray or tan varieties.

  • Black Spots: While the body of a drain fly is typically one of the aforementioned colors, they may have darker black or grayish spots or speckles on their body or wings.

The color of drain flies may be influenced by factors such as lighting conditions and the specific environment they inhabit. Additionally, because they are quite small and often seen in dimly lit areas, their coloration may not always be immediately noticeable. Their small size and moth-like appearance are more distinctive characteristics that can help identify them.

What Do Drain Fly Eggs Look Like

Drain fly eggs are tiny and difficult to see with the naked eye due to their small size and translucent appearance. They are typically laid in moist, organic-rich environments, such as the slime and organic debris found in drains, sewage systems, or stagnant water. Here is a detailed description of what drain fly eggs are like:

  • Size: Drain fly eggs are incredibly small, measuring only about 0.5 millimeters in length.

  • Shape: They are oval-shaped, resembling tiny elongated capsules.

  • Color: Drain fly eggs are nearly translucent or pale white in color. This transparency makes them challenging to spot against the organic material where they are laid.

  • Location: Adult female drain flies typically lay their eggs in clusters on or near the surface of the moist organic matter in their breeding sites. These breeding sites are often found in damp, slimy, and dark areas like drainpipes, sink or shower drains, sewage systems, and similar locations.

  • Quantity: A single female drain fly can lay hundreds of eggs during her reproductive period. These eggs hatch into drain fly larvae after a few days.

Because drain fly eggs are so small and inconspicuous, they often go unnoticed until they hatch into larvae. It's essential to address the underlying conditions that attract drain flies, such as the accumulation of organic material in drains or plumbing fixtures, to prevent future infestations, as eggs are a part of their life cycle.

Request Your Free Inspection

Complete the form below to request your free inspection.

Customer Reviews

Technician was on time, called before arriving- answered all my question and was kind and treated our place with care. I’ll definitely use the service for other properties and will recommend.

Te Y. | 23 June 2021
two parents with two kids