The puparia are about 2.6 mm long and 0.9 mm wide. At the hind end, the spiracles resemble stiff antennae. On the front, the anterior spiracles stick out sideways like microscopic horns. The puparia are curved toward the top side of the developing fly. Scatella stagnalis also occurs widely in Europe and Asia.
Most species naturally occur on muddy or marshy lake shores and intertidal zones of beaches.
Food Plants - Adult and immature shore flies feed on microscopic algae, dinoflagellates, bacteria, cyanobacteria, and other unicellular forms. Damage - Neither adult nor immature shore flies feed upon ornamental plants. Sometimes shore flies become so abundant in greenhouses that the sheer numbers of flies becomes a deterrent to customers browsing or even employees working. Life History - Scatella shore flies are commonly found in greenhouses where they breed in algae growing on the potting mix, pots, benches and floors. Females scatter eggs right on the surface of the potting mix.