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Talitrus saltator has distinctive antennae. I think your images suggest this species (although the antennae aren't too clear). The mottled coloration and white eye patches are interesting, but there are a number of images on the internet which also show these features and seem to be genuine examples of this species (ie also showing the distinctive antennae of Talitrus).
Lat/Lng: 55.56945, -1.64316
OS grid ref: NU226306
Specimens were trapped with sand and water in a litter item - icecream box.