The commonest blue damselfly in much of boreal Europe, but very local relict populations further south. Males are recognised by their greenish hue and the black spearhead markings on the basal abdominal segments.
Total: 31-33 mm.
Abdomen: 22-26 mm.
Hindwing: 16-22 mm.
Wide variety of pools and lakes in the north, but restricted to somewhat acidic and oligotrophic or mesotrophic habitats in much of its range. Favours well-vegetated borders, e.g. with sedges.
From May to July. Most abundant in May and June.