Identification
Fungus gnats vs. fruit flies, drain flies, and springtails
Written by Mustafa Ayan Fact-checked against university extension/IPM sources Last reviewed: September 19, 2026
Direct answer
Fungus gnats hover over houseplant soil and are dark with long, mosquito-like legs. Fruit flies are tan with red eyes and cluster around ripening produce or drains. Drain flies are fuzzy, moth-shaped, and sit still near sinks and floor drains. Springtails aren't flies at all — they're tiny, wingless, and jump rather than fly, usually on soil that's staying too wet. Where you find them, more than what they look like, is usually the fastest way to tell them apart.
| Pest | Appearance | Behavior | Breeds in |
|---|---|---|---|
| Fungus gnats | Slender, dark gray to black, mosquito-like silhouette with long legs and a single pair of clear wings. | Weak, wandering fliers. Rest on soil, pot rims, or nearby walls; lift off when a pot is watered. | Usually moist potting soil; can also occur in other damp organic sites |
| Fruit flies | Small, tan to brown, with a rounder body and noticeably red eyes. | Strong, darting fliers. Found around ripening produce or anywhere fermenting residue collects. | Commonly fruit, trash, and fermenting organic material |
| Drain flies (moth flies) | Small and fuzzy with broad, moth-like wings held in a tent shape at rest. | Weak, short hopping flights. Rest on walls and fixtures near sinks, showers, or floor drains. | Commonly drains and organic buildup in drain traps |
| Springtails | Tiny (under 1/8 in), wingless, gray to white. Not a fly at all — a distinct group of soil arthropods. | Don't fly. Jump or spring when disturbed. Often seen clustered on very wet soil surfaces or floating in a saucer. | Overly wet, organic-rich soil or decaying plant matter |
Why the distinction matters
Fungus gnat treatments target moist soil and larvae underground — they won't touch a fruit fly problem coming from a bowl on the counter, and vice versa. Treating the wrong pest is one of the most common reasons a "fix" appears not to work. If you're still unsure, use the interactive identifier, which walks through the same distinctions with your specific situation.
Confirmed it's fungus gnats? Start the full guide