Orange-tip Anthocharis cardamines
Orange-tips are reasonably common wherever the preferred food plants Garlic Mustard or Cuckooflower grow. Males are distinctive and very obvious in flight but, at rest with closed wings, both sexes become hard to see as the mottled green and white underside of the hind-wing is excellent camouflage. Early spring butterflies, Orange-tips are rarely seen after mid June.
Images L-R: male; underside; female
Flight period: April to June