Microdon analis (Macquart, 1842)
Microdon eggeri Mik in Stubbs & Falk (1983).
Biology & ecology:
This is a woodland and heathland species . It is also reported from areas of windblow within former conifer plantations that were felled by the Great Storm of 1987. The larva is a predator of ant broods within the nests of the black ant Lasius niger (agg.). Its characteristic domed shape and marginal fringe provide protection from ant bites. The larva is usually found in ant colonies within Scots Pine Pinus sylvestris and Birch Betula sp. stumps and can be numerous. Adults are rarely encountered and are most frequently found by sweeping as they are not regular flower visitors.
The distribution is disjunct with populations in southern England on the heaths of Berkshire, Surrey, Sussex, Hampshire and Dorset, and again in the Highlands of Scotland where it occurs in Caledonian pine forest at localities such as Rothiemurchus Forest, Glen Affric, the Black Wood of Rannoch and Loch Garten.
Status & conservation:
It occurs widely across Heather Calluna vulgaris heath with Scots Pine in southern England and in similar locations in Caledonian pine forest. No obvious trend. There are records from 55 post-1985.