Andy Sands / Small blue butterfly (Cupido minimus) mating pair, Hertfordshire, England, UK, May

Andy Sands / Small blue butterfly (Cupido minimus) female laying eggs among flowers of Kidney Vetch (Anthyllis vulneraria), Hertfordshire, England, UK, May

Lorraine Bennery / Mating pair of Small Blue Butterflies (Cupido minimus) and Chalkhill blue butterflies (Lysandra coridon) mating, Hautes-Alpes, France, May.

Rod Williams / Small blue butterfly (Cupido minimus) male hoping to mate with female on their foodplant, kidney vetch Hutchinson's Bank, New Addington, London, England, UK. June.

Russell Cooper / Small blue butterfly (Cupido minimus) resting on a grass stem, Surrey, England, UK. June.

Andy Sands / Small Blue butterfly (Cupido minimus) Roosting on grass stem, Bedfordshire, England, UK, July

Andy Sands / Small Blue butterfly (Cupido minimus) roosting on grass stem, Bedfordshire, England, UK, July

Rod Williams / Small blue butterfly (Cupido minimus) male, Britain's smallest butterfly, Hutchinson's Bank, New Addington, London, UK May

Rod Williams / Small blue butterfly (Cupido minimus) male feeding on its foodplant Kidney vetch (Anthyllis vulneraria) Hutchinson's Bank, New Addington, London, UK. June

Rod Williams / Male Small blue butterfly (Cupido minimus) resting with wings open on leaf, Hutchinson's Bank, New Addington, London, England, June.

Rod Williams / Male Small blue butterfly (Cupido minimus) resting with wings open on leaf, Hutchinson's Bank, New Addington, London, England, June.

Russell Cooper / Male Small blue butterfly (Cupido minimus) resting on a leaf, Surrey, England, UK, June.