Purple Hairstreak
Favonius quercus
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Lives in the tops of oak trees and feeds on honeydew — which is why almost nobody sees one.
A small butterfly, silvery-grey beneath with a fine white streak, and iridescent purple above — a full sheen on males, a smaller purple patch on females. Purple hairstreaks live in oak woodland, and around Dumfries they are present wherever there are mature oaks. They are almost certainly under-recorded, because the entire life of the species happens twenty metres up.
Behaviour
Adults rarely come down. They spend their days in the oak canopy feeding on aphid honeydew rather than flowers, and are best found by scanning the treetops on a still, warm evening in late July, when small silvery butterflies flutter around the highest branches. Eggs are laid at the base of oak buds and overwinter there until the buds burst.
When to see it
Quick facts
- Family
- Blues and coppers (Lycaenidae)
- Wingspan
- 3–3.5 cm
- Status
- Native; widespread in oak woodland but under-recorded
Photo by Charles J. Sharp, CC BY-SA 4.0, via Wikimedia Commons