There are 41 Species of solider beetle in the UK. The larger species (Subfamilies: Cantharinae & Silinae) are often starkly coloured with blacks, reds and yellows. These colours reminded naturalists of the past of red-jacketed soldiers and this is how this beetle family acquired its English common name.
COMMON RED SOLDIER BEETLE : Rhagonycha fulva.
The common red soldier beetle is also misleadingly known as the bloodsucker beetle and popularly known in England as the hogweed bonking beetle. Our example, true to form, was found on a hogweed flower,although alone.
Adults feed on aphids, and also eat pollen and nectar. Larvae prey on ground-dwelling invertebrates, such as slugs and snails, and live at the base of long grasses. The adults, which are active between the months of June and August, spend much of their short lives mating and can often be seen in pairs. [Wiki].
A GUIDE TO BRITISH SOLDIER BEETLES : https://drive.google.com/file/d/0B008cp9g-Pm8a3pET1BfejFERm8/view?resourcekey=0-t60fxPBMyH7krtxcdaUItg
WIKIPEDIA : https://en.wikipedia.org/wiki/Rhagonycha_fulva