Shore fly
flies of the genus Scatella are a common greenhouse pest found throughout the United States, Canada and northern Mexico. In Europe and Asia, the species Scatella [...] muddy lake shores and intertidal zones, and they breed readily in other moist environments. In greenhouses, adults feed on algae and their larvae on algae [...] other unicellular organisms, they do not cause any direct damage to plant production. However, they are considered a nuisance pest because the flies : Leave