I found these two engrossed in a fight to death and thought it made an amazing picture. I think its a (Dysdera crocata aka the spider) and a greenbottle (Lucilia Caesar). Would love feedback.
No identification made yet.
No interactions present.
The red carapace on the spider looks like Dysdera, but I don't think they spin webs to catch prey (they can produce silk however, as they produce a silken cell which they live in during the day). It may just be pinching the fly out of another spider's web, of course.
I agree with Rob that this would be unusual behaviour for Dysdera, which is usually ground-dwelling and preys largely on woodlice rather than flies, but I can't really tell from the photo what species it might be.
The fly could be a Lucilia greenbottle, but there are very similar-looking green flies in other families as well.
Entomologist and biological recorder
Lat/Lng: 50.9, -4.6
OS grid ref: SS2314