Osmia leaiana – Allotment

Osmia leaiana

Restricted to England and Wales. It is less frequently found than O. caerulescens, but occurs in similar habitats. Overseas: Europe, although at higher altitudes in southern areas; also north-west Africa, also at higher altitudes.
The species may be encountered almost anywhere in England and Wales, but it requires cavities in dead wood, walls or cliffs for nesting.
Flight period
This species may be found between May and August.
Nesting biology
Nests in a variety of cavities, in walls, cliffs and dead wood. The nest closure and partitions are made from chewed plant material, bright green when fresh, which dries to a dark-brown, granular appearance.
Flowers visited
Recorded visiting a wide variety of flowers from a number of different plant families for nectar, but oligolectic on Asteraceae for pollen.
The cleptoparasitic bee, Stelis phaeoptera, has been recorded as utilising this bee as a host (Westrich, 1989). It is likely that it is also attacked by the cuckoo-wasp Chrysura radians (Morgan, 1984)…BWARS