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Shore Flies – Scatella stagnalis

Shore Flies (Scatella stagnalis) Common Name: Shore Flies Latin Name: Scatella stagnalis Appearance:
  • Shore flies are generally found near water because damp to wet environments and the presence of algae and moss in potting soil, pots, table surfaces, and floors promote their growth.
  • The 0.1 mm long bean-shaped eggs are deposited on moist soil surfaces with algae.
  • The 0.5 mm larvae are brownish with exceptional breathing tubes at the back and are found in the top layer of the growth material. In the earth, the larvae pupate.
  • Pupae measure 2 to 3 mm in length and are brown.
  • Adults are 0.5 cm long, with small legs, short antennae, and black wings with clear spots.
Territory: Shore flies of the genus Scatella may be found across the United States, Canada, and northern Mexico. Damages caused by Shore Flies: Shore flies (Scatella tenuicosta) do not affect plants directly since they feed on green algae. However, their large numbers can transmit plant diseases and be a nuisance to greenhouse employees. Frass deposited on the leaves or flowers of ornamental crops, lettuce, and herbs cause aesthetic harm as well, and it can occur on such a wide scale that development, particularly of early cuttings, can be impeded. Life history and habits: Shore flies haphazardly deposit their eggs on algae or damp growth substrate. The eggs hatch in 2 to 3 days, and the larvae feed on algae just beneath the surface of the growth material for about a week before entering the pupal stage. The larvae begin consuming algae shortly after hatching. Before becoming adults, they go through three larval stages and one pupal stage. After four to five days, adult shore flies emerge from the pupae.