Moth fly (drain fly), likely a Psychodidae larval case or pupa

Moist organic films in drains, bathroom plumbing, sewage systems, and damp soil. The pictured object appears to be a case or pupa rather than an adult fly.

Larvae feed on bacteria, fungi, algae, and decomposing organic matter in drain slime. Adults have short lifespans and take little or no food, sometimes consuming liquids.

Larvae develop in stagnant, wet organic deposits; adults are weak, fuzzy fliers often resting on nearby walls. Several generations may occur annually indoors where drains remain moist.

Generally harmless and nonbiting, though large indoor infestations indicate dirty or poorly draining plumbing. Larvae help decompose organic matter, but may occasionally contaminate food or surfaces.