| Family | Lycaenidae |
|---|---|
| Subfamily | Theclinae |
| Genus | Satyrium |
| Species | pruni |
| Authority | (Linnaeus, 1758) |
| English Name | Black Hairstreak |
| European Red List 2010 | Least Concern (LC) |
|---|---|
| EU 27 Red List 2010 | Least Concern (LC) |
| European Red List 2025 | Vulnerable (VU) |
| EU 27 Red List 2025 | Vulnerable (VU) |
| Habitats Directive | |
| Bern Convention | |
| CITES |
The Black Hairstreak can be found where there are Blackthorn (Prunus spinosa) bushes growing. This may be in moderately dry woodland, or in a hedgerow, or on a woodbank, but it also occurs on solitary groups of Blackthorn bushes. Places with brambles are favorable, providing the nectar the butterflies need. The eggs are laid on Blackthorn (Prunus spinosa), but sometimes other Prunus species are used. The female chooses twigs that will flower the next spring. The small caterpillars that develop, pass the winter in the eggshell. When they emerge, they feed on the buds and flowers. When the caterpillars are fully-grown, they pupate. The black and white pupa, suspended in a silken girdle from a twig, looks very like a bird dropping, an attempt to avoid predation. The Black Hairstreak is single-brooded.
Albania / Austria / Belarus / Belgium / Belgium: Wallonia / Bosnia and Herzegovina / Bulgaria / Croatia / Czechia / Denmark (Regionally Extinct) / Estonia / Finland / France / France: Mainland / Germany / Greece / Greece: Mainland / Hungary / Italy / Italy: Mainland / Latvia / Lithuania / Luxembourg / North Macedonia / Moldova / Montenegro / Netherlands (Irregular Vagrant) / Poland / Romania / European Russia / Serbia / Serbia: Serbia / Serbia: Kosovo / Slovakia / Slovenia / Spain / Spain: Mainland / Sweden / Switzerland / Ukraine / United Kingdom / United Kingdom: Great Britain /