the common brimstone (gonepteryx rhamni) on the buttonbush (cephalanthus occidentalis) flowering

animal gonepteryx rhamni wildlife america beautiful bloom blooming blossom botany brimstone bug butterfly buttonwillow buttonbush cephalanthus occidentalis closeup common creature delicate entomology environment flora floral flower garden gardening geometrical habitat honeybells inflorescence insect invertebrate macro male medicinal nature ornamental outdoors pattern petals pieridae plant shrub spherical summer white wild wings yellow button-willow honey-bells flowering arranged