Sciarid flies (fungus gnats)
Also known as Fungus gnats as they are commonly found in compost where mushrooms are cultivated. A nuisance pest common to house plants. The adult flies are greyish-brown. These small flies can be seen running over the surface of pot plants or flying slowly around the plant when disturbed and alighting back on to the leaves.
The larvae of sciarid flies are small white wriggely maggots with black heads. They can be seen just under the compost surface where they feed mainly on decaying plant material (compost). House plants can be sprayed with Provado Ultimate Bug Killer - aerosol can which may control the adult flies.
Cultural measures: Adult flies can be trapped by hanging up sticky greenhouse fly catchers close the pots.