Cheilosia urbana (Meigen, 1822)
Cheilosia praecox (Zetterstedt, 1843). Cheilosia globulipes Becker was considered as a doubtfully distinct species by Stubbs & Falk (1983).
Biology & ecology:
Females oviposit on leaf axils of Mouse-ear Hawkweed Hieracium pilosella. Upon hatching, C. urbana larvae migrate to the soil and feed externally on the roots (Grosskopf, 2005). Mature larvae pupate in the soil close to the surface. Adults are usually seen visiting flowers such as sallow Salix sp. catkins, early in the spring in woodland edges (deciduous and coniferous), scrub and damp grassland. Males tend to hover in sheltered, sunny locations whilst females can be found hovering over short turf with Cats Ear Hypochoeris radicata, hawkbits Leontodon sp. and hawkweeds Hieracium sp.
Although generally scarce, this species is widespread in Wales and England north to the Humber, and there are recent records from Cumbria and Northumberland and a scatter of records from Scotland. It is possibly missed by some recorders because of its early flight period.
Status & conservation:
There appears to have been a decline in occurrence over the past 25 years. This may reflect changing recorder effort and abilities, but from our field experience suggests that there may be a genuine decline.