Wingspan 27-32 mm.
Mainly distributed in the south and south-east of England, it occurs locally as far north as northern England.
It inhabits wooded valleys, downland and southern heaths, and flies in September and October.
The larvae feed on beech (Fagus) or field maple (Acer campestre), at first on the buds and subsequently on the flowers and leaves…. UK Moths
This is our largest Sargus (wing length to 10mm). Thorax shiny metallic green, scutellum without spines, veins in the wing quite distinct. The male and female of this species differ considerably in appearance, males are very slim with a metallic green thorax and metallic bronze abdomen (like male Chloromyia formosa but with a much narrower build). Females have a broader build with the base of the abdomen extensively reddish contrasting with a blackish tip bearing blue reflections. Both sexes have orange legs and a pair of whitish spots on the frons just above the antennae.
Low vegetation. Adults can be found in a variety of open and wooded habitats, usually sunbathing on foliage in sheltered spots.
When to see it
August to early November.
The larvae have been reared from cow dung, compost, rotting vegetation and decaying fungi…Nature spot
This is the largest Colletes hederae aggregation I have found , the whole ploughed trough along the path was filled with bees and their burrows.
I have posted information on these relatively new bee to the UK before which you will find in the link below
Colletes hederae information