Apatura iris, the purple emperor, is a Palearctic butterfly of the family Nymphalidae.
Description
Adults have dark brown wings with white bands and spots, and a small orange ring on each of the hindwings. Males have a wingspan of , and have a purple-blue sheen caused by iridescence that the slightly larger (80–92 mm) females lack. The larvae (caterpillars) are green with white and yellow markings, and have two large "horns" at the anterior end and a smaller one at the posterior.
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Apatura iris MHNT CUT 2013 3 18 Compiegne Dos.jpg|Dorsal side
Apatura iris MHNT CUT 2013 3 18 Compiegne Ventre.jpg|Ventral side
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Habits
Females spend most of their lives in the tree canopy, favouring dense and mature oak woodlands, coming down only to lay their eggs on the small willow bushes that grow in clearings and bridleways. Males also spend much of their time in the tree tops, defending their territory from rivals, though they will sometimes descend to drink from puddles or feed. Unlike most butterflies, the purple emperor does not feed from flowers but instead on the honeydew secreted by aphids, sap oozing from oak trees, and on dung, urine, and animal carcasses. Heslop et al. noted that the males' penchant for roadkill can often cause them to be killed by cars. (Poplar is a more common food plant in continental Europe than in the British Isles.
South noted that it had not been recorded from Scotland, and only doubtfully from Ireland, adding that "in Wales it is only found in Monmouthshire."