Gyrinus urinator

This came to light. I immediately suspected it wasn't substriatus, the Gyrinus I see most frequently. Although I didn't discern the detail of the elytral pattern on first look, the overall impression was of a more bronzy, less black, beetle than other whirligig beetles I'd seen before.

female Gyrinus urinator showing scutellum, close-up of elytra and ovipositor, Cooper Street, near Ash (Kent, UK), 16th July 2026