Syrphus torvus Osten-Sacken, 1875
Biology & ecology:
The larva feeds on a wide range of ground layer and arboreal aphids. Adults visit a wide range of flowers and often found around trees, typically along woodland edge and hedgerows, as well as in orchards and mature gardens. Like S. ribesii, it is multiple-brooded and has a long season, but it tends to show marked, and quite brief peaks of abundance in the spring and again in mid-summer.
This hoverfly (especially the female) is probably overlooked amongst other Syrphus species. There has been a tendency to think of it as a southern species, but recent records suggest that it is also common in Scotland.
Status & conservation:
General trends suggest a decline in occurrence. In some years this can be an abundant species, especially during the early spring flight period, but in other years it appears scarce or almost absent.