Pretty sure this is a hoverfly but can't find a match for abdomen marking. Maybe juvenille?
No interactions present.
Hoverflies don't have juveniles. Flies have 4 distinct life stages - egg, larva (a maggot), pupa and adult. Thus any fly is always an adult. However, freshly emerged adults (teneral specimens) can be paler/different in colour (perhaps this is what you meant?).
BMIG website: www.bmig.org.uk (centipedes, millipedes & woodlice)
BMIG Newsletters ~ www.bmig.org.uk/view/resource/bmig-newsletter
BMIG Bulletins ~ www.bmig.org.uk/view/resource/bmig-bulletin
Cheers, yes ID looks spot on.
Seemed to have a good late summer, as I saw it far more than normal, this year.
I am not really bothered myself, Rob, but iSpot etiquette is that you don't add the ID again yourself, once another has added it for you.
My Flickr photos...
Lat/Lng: 51.8011, -1.4091
OS grid ref: SP408115