Large Blue (Maculinea arion)
Successfully reintroduced to sites in the Poldens where it is slowly extending its range due to active habitat creation and management. A quite distinctive species, the sexes are rather similar, the male being slightly smaller and with less heavy spotting on the wings.
Because of its scarcity, a distribution map showing sites is not given but Somerset Wildlife Trust's Green Down reserve and Collard Hill, a National Trust site are both usually reliable locations.
Images L-R: female egg-laying on wild thyme, the young caterpillar's foodplant; underside
Flight period: usually mid June to mid July.