“Jumping flies” is a loose term that describes several very different insects. The most common culprits are phorid flies (tiny flies that scuttle and hop across surfaces instead of flying), cheese skippers (fly larvae that literally fling themselves through the air), and psyllids (plant-feeding insects sometimes called jumping plant lice). Which one you’re dealing with depends on where you spotted it: your kitchen, your food, or your garden.
Phorid Flies: The Scuttling Kitchen Invader
Phorid flies are the insects most people mean when they describe small flies that seem to jump or dart across countertops. These tiny flies, only about 1/16 to 1/4 inch long, prefer running erratically over surfaces rather than taking flight. That jerky, sprint-and-stop movement earns them the nickname “scuttle flies” and makes them look like they’re hopping. Their hunched thorax also gives them the name “hump-backed flies.”
They breed in moist, decaying organic matter, and the list of potential breeding sites inside a home is long: drain pipe buildup, garbage disposals, rotting fruit and vegetables, pet waste, dirty mop heads, food scraps trapped under appliances, potted plant soil, and trash cans that haven’t been scrubbed out. Outdoors, they gravitate toward compost piles, decomposing animals, sewage-contaminated soil, and wet landscape clippings. They also have a well-documented habit of breeding around human remains, which earned them the additional name “coffin flies.”
Because phorid flies reproduce in hidden organic buildup, spraying them does almost nothing. The adults you see on your counter are a symptom, not the problem. Elimination means finding and removing the breeding source. Start by checking drains, cleaning under and behind kitchen appliances, scrubbing trash receptacles, and disposing of any decaying organic material around the outside of your home. Once the source is gone, the adult flies die off within days.
Cheese Skippers: Larvae That Launch Themselves
Cheese skippers are the larvae of the cheese fly, a small species attracted to cured meats, aged cheeses, and other protein-rich foods. The larvae are the real acrobats. When disturbed or ready to move to a new location, a cheese skipper hooks its mouth into its own rear end, contracts its muscles, and releases, flinging itself up to 4.7 inches (about 12 centimeters) through the air. This catapult-like motion is what gives them the name “skippers.”
You’re unlikely to encounter cheese skippers in a modern kitchen unless cured or salted foods have been stored improperly for an extended period. They’re more commonly a concern in artisanal cheesemaking, charcuterie aging rooms, and occasionally in neglected pantry items. If you find small, wriggling larvae that leap when you poke at them on or near aged food, cheese skippers are the likely culprit. Discarding the infested food and thoroughly cleaning the storage area resolves the problem.
Psyllids: Jumping Plant Lice in the Garden
If the “jumping flies” you noticed are on your plants rather than in your kitchen, they’re probably psyllids. These tiny sap-sucking insects look like miniature cicadas, measure 1/10 to 1/5 inch long, and hold their wings tent-like over their bodies. They have powerful hind legs and will spring away quickly when disturbed, which is why they’re commonly called jumping plant lice.
Each psyllid species feeds on only one plant or a narrow group of related plants. Common targets include citrus, pear, potato, tomato, eucalyptus, boxwood, and pepper trees. Females lay eggs that hatch into flat, oval nymphs. The nymphs pass through five growth stages before becoming winged adults, and in warm weather the entire cycle from egg to adult takes only a few weeks. Most species produce three to five generations per year.
The damage psyllids cause resembles what you’d see from aphids or whiteflies. Look for sticky honeydew coating leaves, black sooty mold growing on that honeydew, curled or distorted new growth, premature leaf drop, and in some species, waxy crystallized covers called “lerps” on leaf surfaces. Several psyllid species are serious agricultural pests, particularly on citrus and pear crops, because beyond direct feeding damage they can transmit plant diseases.
How to Tell Them Apart
- Location: Phorid flies appear near drains, trash, and decaying material indoors. Cheese skippers show up on aged or cured foods. Psyllids live on plants.
- Size: Phorid flies are 1/16 to 1/4 inch. Psyllids are 1/10 to 1/5 inch. Cheese skipper larvae are small maggots, not winged insects.
- Movement: Phorid flies scuttle in short, erratic dashes across flat surfaces. Psyllids leap from leaves using strong hind legs, then fly. Cheese skipper larvae curl and launch themselves from food surfaces.
- Wings: Phorid flies have a distinctive humped back and visible wings but rarely use them. Psyllids hold their wings rooflike over their bodies and resemble tiny cicadas. Cheese skipper larvae are wingless.
Getting Rid of Jumping Flies
For phorid flies, sanitation is everything. Clean drain pipes with an enzyme-based drain cleaner or a stiff brush to remove the organic film where larvae develop. Pull out appliances and clean underneath them. Wash trash cans inside and out. Remove pet waste promptly. Outdoors, clear away rotting vegetation, old mulch, and any organic debris that stays consistently moist. Sticky traps and apple cider vinegar traps can catch adults, but they won’t solve the problem if the breeding source remains.
For cheese skippers, discard all infested food, clean storage areas thoroughly, and make sure cured or aged products are properly sealed or stored in controlled environments. These infestations are rare in typical households.
For psyllids, management starts with inspecting new plants before bringing them into your garden. Strong water sprays can knock nymphs off leaves. Pruning heavily infested shoots removes large numbers of immatures at once. Natural predators like lady beetles, lacewings, and parasitic wasps help keep populations in check outdoors. Horticultural oils and insecticidal soaps work on nymphs when applied directly, though they need to make contact to be effective.