The brimstone is regularly seen in SE Carmarthenshire, albeit in small numbers. Its food plants - buckthorn Rhamnus carthartica and alder buckthorn Frangula alnus are very localised, the former on the thin ridge of Carboniferous limestone that delineates the coalfield edge and the latter sparingly in hedgerows on often rather peaty soils. Alder buckthorn has been included in landscape plantings and these have now led to increased numbers of brimstones encountered. Barry Stewart made an interesting observation many years back when he was working at WWT Penclacwydd - he noticed that our local brimstones preferred alder buckthorn for their egg laying. I`ve since grown on many plants from berries, the now-mature bushes that I`ve planted around and in my garden often attract brimstones and their speckled green caterpillars can sometimes be found. The photo shows a female that was initially attracted to a Buddleja in my garden at Pwll, Llanelli and I was in the process of trying to sneak up to take a photo when she kindly landed on a flower of Knautia macedonica right at my feet- very obliging!