Fungus gnat (likely adult)

Moist soil, decaying organic matter, compost, and damp indoor areas, especially around overwatered houseplants.

Adults consume little, sometimes taking plant fluids or fungi; larvae feed mainly on fungi and decaying organic material, and may damage fine plant roots.

Small, dark, weak-flying adults often run or hover near soil and are attracted to light. Larvae develop in moist substrates, completing the life cycle in roughly 3–4 weeks under favorable conditions.

Generally harmless to people and pets and do not bite. Larvae aid decomposition but can stress seedlings and houseplants when populations are high.