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 darvasica × "P. cerasifera"). Prunus darvasica Prunus darvasica, the Darvaz plum, is rare plant endemic to Tajikistan. It is found in the Tajik portion of the Pamir Mountains, the Darvoz Range. There, the plants grow as shrubs 1.5-2.5m tall. The fruit are small (2cm) but otherwise typical plums, nearly black, with a blue waxy coat. The pit is brown. The fruit is edible and can be made into jam or compote. It is suspected that "P. darvasica" is of hybrid origin, as it is a tetraploid with 48 (or 32, depending on the source) chromosomes, possibly the result of "P. domestica"