Cheilosia soror (Zetterstedt, 1843)
Cheilosia ruffipes (Preyssler, 1793).
Biology & ecology:
The larva is believed to inhabit fungi, and this species is reported to have been bred from truffles. Adults are strongly associated with Chalk and limestone, where they have been found feeding on the flowers of white umbels, especially Hogweed Heracleum sphondylium and Wild Parsnip Pastinaca sativa, in grassy rides and glades.
Records are widely scattered from chalk and limestone areas, mainly in eastern England, as far north as Morecambe Bay. Records from London suburbs suggest that it may be more widely distributed, possibly influenced by the calcareous content of concrete and rubble in urban areas.
Status & conservation:
Occurrence over the past 25 years appears to have increased markedly. This seems to be a real change as the Cheilosini are generally poorly recorded by modern recorders, but it may also reflect increased effort in the limestone areas of Northamptonshire which were previously unworked. Recorded from 239 hectads since 1985.