Dark-winged fungus gnat (likely)

Moist potting soil, decaying organic matter, greenhouses, and damp indoor areas. Adults may wander onto floors and windowsills.

Larvae feed mainly on fungi, algae, and decaying organic material in soil; some may nibble tender roots. Adults primarily consume liquids or do not feed significantly.

Adults are weak fliers and often run or make short flights; larvae develop in moist soil and organic debris. Infestations commonly arise from overwatered houseplant soil.

Generally harmless to people and pets, and adults do not bite. Larvae help decompose organic matter but can damage seedlings and roots when abundant.