Family Anyphaenidae (Buzzing spiders)
Body length 4-7 mm.
There is only one genus and 2 species in Britain, which look very similar and the only way to tell them apart is with a microscope. It has two pairs of distinct brown markings on the abdomen, almost looking like chevrons. They are called buzzing spiders for the way the males vibrate their abdomen against the surface of leaves in order to attract females.
They hunt by running down their prey amongst the foliage of trees and bushes.
Seen April to October, and found in the foliage of trees and bushes. Common and widespread in the south of Britain, less so further north.
Field notes: I am pretty confident this is the correct species as the other one is confined to London. I found this one on my Fatsia, and it appeared to be hunting and eating spiderlings of a another species of spider, the Cucumber Green Spider (Araniella cucurbitina sensu lato).