Ferdinandea ruficornis (Fabricius, 1775)
Biology & ecology:
The larva filter feeds on yeasts and bacteria in sap runs on a variety of trees. F. ruficornis is thought to be one of a suite of species that are to some degree associated with the workings of the Goat Moth Cossus cossus, but it is unlike that this is an obligate association as the fly does occur at localities where the moth has not been found. Adults are very difficult to locate, but are occasional flower visitors.
This is largely an English species with just a single record from Wales. It is mainly southern, almost entirely confined to a line between the Humber and the Ribble, but with a single outlier in North Yorkshire.
Status & conservation:
There has been no significant change in occurrence.