Insect in rocky area of moorland valley, about 20mm in length, can run quite fast.
No interactions present.
As soon as I'd clicked, I remembered S. erythropterus. There's difference in pubescence which I doubt would show on the photograph, but it has the scutellum white with pubesence, whereas the scutellum of S. dimidiaticornis and S. caesarea is black. I don't think the scutellum of yours is pale, is it?
Like the other 'dimidiaticornis' at http://www.ispot.org.uk/node/329036 this is erythropterus, and for the same reason.
As per Mydaeas comments
There is a super illustration here Staphylinus erythropterus
and for comparison Staphylinus dimidiaticornis
Whats Happening with Nature ??? Visit the Nature Blog
Supporting FEET Conservation work & Biodiversity Recording
Yes, I believe so but I have not shifted Likely.
It's not an easy call for someone way outside their comfort Zone (I am) but I am quite happy with what I see.
A decent photo and some good interactive Comments.
Where are the entomologists? http://www.ispotnature.org/node/691186
Lat/Lng: 55.3946814, -2.3054391
OS grid ref: NT807112
Rocky area near Buckham's Wall Burn