Chalcosyrphus nemorum (Fabricius, 1805)
Xylota nemorum (Fabricius, 1805) in Coe (1953), Xylotomima nemorum (Fabricius, 1805) in Kloet & Hincks (1976).
Biology & ecology:
This species is generally found in wet, wooded situations, but adults can also occur on sunny vegetation at the edges of woods and along rides. They may be regular visitor to buttercups Ranunculus sp. and other yellow flowers. The larva is found in accumulations of sap under the bark of roots of water-sodden, dead standing trees and fallen trees or branches lying in water. A wide range of tree species are utilised.
This is primarily a lowland species. It is widely distributed south of a line between the Ribble and the Humber, becoming scarcer northwards. Records extend as far north as Sutherland.
Status & conservation:
There has been some decline in occurrence over the past 25 years in south-east England, but overall little change.