Shore fly

The shore fly (genus Scatella) belongs to the order Diptera and the family Ephydridae. These insects are common pests in greenhouse environments where high humidity and moisture levels promote their rapid proliferation and survival throughout the year.

They primarily affect nursery crops, young seedlings, and various greenhouse plants. Unlike fungus gnats, shore flies are primarily associated with the presence of algae, which they use as a primary food source, although they can also inhabit wet growing media and debris.

The biology of Scatella is intrinsically linked to moisture. Adults lay their eggs in wet substrates or on algae-covered surfaces. Larvae develop through several instars within the moist medium, and while they feed largely on algae, their feeding activity can disturb roots or weaken plant structures.

Damage is often indirect but significant; shore flies are known to spread fungal spores, such as Pythium, between plants. Their presence is also a nuisance and indicates poor sanitation or excessive irrigation practices within the greenhouse facility, which can exacerbate other plant health issues.

Effective management requires an integrated approach. Essential strategies include:

• Improving drainage and reducing surface moisture.
• Removing algae buildup on greenhouse floors and benches.
• Using biological control agents such as predatory mites or nematodes.
• Applying compatible insecticides only when thresholds are exceeded.