Brimstone

Perfect camouflage, look quickly you'd think it was a leaf then it flutters & you realise it's a butterfly. Usually one of the first spotted butterflies in Spring in the UK, but more abundant around my garden when the buddleia is flowering. Brimstone's foodplants are buckthorn & Alder buckthorn.

A small fact: There is a view that the word 'butterfly' originates from the yellow colour of male Brimstones & their nickname is yellow-bird butterfly.