''Eristalinus aeneus'' (Scopoli, 1763), the common lagoon fly, is a fairly common species of

syrphid fly Hover flies, also called flower flies or syrphid flies, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while ...

observed throughout the United States and Europe. Hoverflies can remain nearly motionless in flight. The adults are also known as flower flies for they are commonly found on flowers, from which they get both energy-giving nectar and protein-rich

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametop ...

. The larvae occurs along shorelines in rock pools containing large amounts of decaying seaweed.

Description

''For terms see

Morphology of Diptera Dipteran morphology differs in some significant ways from the broader morphology of insects. The Diptera is a very large and diverse order of mostly small to medium-sized insects. They have prominent compound eyes on a mobile head, and (at most) ...

'' 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 Southern Europe it has five strong grey 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 (2003). The larva is figured by Hartley (1961).

Distribution

The distribution of this species is

cosmopolitan Cosmopolitan may refer to: Food and drink * Cosmopolitan (cocktail), also known as a "Cosmo" History * Rootless cosmopolitan, a Soviet derogatory epithet during Joseph Stalin's anti-Semitic campaign of 1949–1953 Hotels and resorts * Cosmopoli ...

inaturalist map

Biology

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''.de Buck, N. (1990) Bloembezoek en bestuivingsecologie van Zweefvliegen (Diptera, Syrphidae) in hetbijzonder voor België. ''Doc.Trav.'' IRSNB, no.60, 1–167. The flight period is April to October, and it overwinters as an adult. In the north, the larvae of ''E. aeneus'' occur in freshwater seapages 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.

References

External links

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External images
Diptera of Europe Eristalinae Insects described in 1763 Taxa named by Giovanni Antonio Scopoli {{Syrphidae-stub