Black hairstreak forewings. The most conclusive way to distinguish the two is by the row of black spots accompanying the orange band which the white-letter hairstreak never has. They spend most of their lives in the canopy or in dense scrub, feeding on honeydew, and very rarely come down to ground level. Eggs are laid singly on young blackthorn "Prunus spinosa" growth and it is this stage which hibernates. Although blackthorn is the main foodplant, wild plum "Prunus domestica" and other "Prunus" spp are occasionally used. The caterpillar hatches the following spring, at the end of April, just before the buds open
Prunus speciosa Prunus speciosa Prunus speciosa, the Oshima cherry, Japanese オオシマザクラ (Oshima zakura), is native to Izu Ōshima island and the Izu Peninsula on Honshū near Tokyo, Japan. "Prunus speciosa" is a deciduous tree typically high. The leaves are 5–10 cm long and 3–6 cm broad, with a double-toothed margin, and an acuminate apex. The flowers are 2.5–4 cm diameter, with five white petals, gold stamens and brown sepals; they grow in clusters in the spring, and are hermaphroditic. The fruit is a small black cherry about 1 cm diameter. A tree 8 m in circumference and 800 years old is known