Shore fly
where they also pupate. The adult shore fly is black, about 4 to 5 mm long, and stout with short antennae and short legs. The head of the adult has a pair [...] green algae. However, they can transmit plant diseases and can be a nuisance to greenhouse works by their sheer numbers. Frass deposited on leaves or flowers [...] have grey-brown patches. Although shore flies can occasionally be confused with sciarid flies ( Bradysia paupera & Lycoriella ingenua) , they are more stoutly