Drain Fly Larva

Natural Habitat

Moist environments rich in decomposing organic matter, commonly found in bathroom drains, sewage systems, shower pans, and sometimes near pools or standing water.

Diet & Feeding

Feeds on decaying organic matter, sludge, algae, bacteria, and fungi found in drains and stagnant water.

Behavior Patterns

The larvae are aquatic or semi-aquatic and do not drown. They breathe through a tube on their posterior end. They are often seen wriggling in the slime layer (

Risks & Benefits

Risks: They are nuisance pests and can breed rapidly in dirty drains. While they do not bite, they can mechanically transport bacteria from sewage to other surfaces. Benefits: They help break down decomposing organic material in the ecosystem, though this benefit is negligible in a home setting.

Identified on: 2/14/2026