Stephen Dalton / Brimstone butterfly (Gonepteryx sp) in flight over Buddleia flowers, England, UK

Andy Sands / Brimstone butterfly (Goneopteryx rhamni) Male at rest on Primrose flower, West Sussex, UK April

Adrian Davies / Male Brimstone butterfly {Gonepteryx rhamni) on March thistle UK, Europe

Colin Varndell / Brimstone butterfly {Goneopteryx rhamni} resting on thistle. UK.

David Kjaer / Brimstone butterfly on Pussy willow catkins, UK

Jussi Murtosaari / Brimstone (Gonepteryx rhamni) feeding on Dandelion flower, Finland, September

Jussi Murtosaari / Brimstone (Gonepteryx rhamni) male on Leatherleaf (Chamaedaphne calyculata) Finland, May

Jussi Murtosaari / Brimstone (Gonepteryx rhamni) male, feeding near water, Finland, August

Jussi Murtosaari / Brimstone (Gonepteryx rhamni) male and female butterflies in flight, Finland, May

Paul Harcourt Davies / Brimstone butterfly (Gonepteryx rhamni) feeding on lavender nectar in garden, Podere Montecucco, Orvieto, Umbria, Italy

Loic Poidevin / Brimstone butterfly (Gonepterix rhamni) feeding on lavender, Provence, France

Mark Payne-Gill / Brimstone Butterfly (Gonepteryx rhamni) fresh chrysalis shortly after formation, Studio, Bristol.