Common Lagoon Fly

Appearance

For terms see Morphology of Diptera
The wing length is 6 ·5- 9·25 mm. The eyes are patterned with obvious black spots. Tergites 2 and 3 are completely shiny. The thoracic dorsum has faint greyish stripes. In males the eyes meet on the frons. In females the eyes are bare on the lower half. The hind tibiae have a black ring after middle, and all tarsi with segments 2-4 darkened.

The male genitalia are figured by Pérez-Bañón et al. The larva is figured by Hartley

Distribution

The distribution of this species is cosmopolitan.

Behavior

The habitat for this species is freshwater: coastal lagoons, ponds, slow-moving rivers, streams and irrigation ditches. The species is anthropophilic in southern Europe; towards the northern edge of its range there it is confined to coastal sites.
The species flies very fast and low over ground vegetation, and feeds on yellow composites and white umbellifers: "Aster", "Berteroa incana", "Cistus", "Origanum", "Salix repens", "Taraxacum".
The flight period is April to October. Overwinters as an adult.

In the north, the larvae of "E. aeneus" occur in freshwater seepages and brackish rock pools on the sea coast, but elsewhere they occur in a variety of freshwater habitats, including in association with animal dung and in sewage farms.