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There are 41 British species of Cantharidae, small to medium-sized (2-15mm) soft-bodied species with leathery elytra. They are predatory, ready fliers, and many are be common sights on flowers over the summer, particularly Rhagonycha fulva (Scopoli), which is often very abundant in July and August. There are three subfamilies in Britain.
Cantharinae (24 species) and Silinae (1 species, Silis ruficollis (Fabricius)) are the archetypal soldier beetles: elongate, parallel-sided and coloured red, yellow, black, and navy blue. All have long elytra, completely or nearly completely covering the abdomen.
Malthininae comprises 16 small elongate species, generally blue-black and often with obvious yellow tips to the elytra. All have abbreviated elytra, covering at most half of the abdomen.