Adult length about 32 mm.
Fine-art photographic collection
Enallagma cyathigerum
A blue damselfly whose females change colour strategy and whose life cycle changes with latitude.
About this species
Common Blue Damselfly
Enallagma cyathigerum(Charpentier, 1840)
Information reviewed15 July 2026
Enallagma cyathigerum is one of the most widespread Palearctic damselflies. Its aquatic larvae develop in still or slow-moving freshwater, while adults hunt small flying insects around ponds and lakes.
Taxonomy
Animalia · Arthropoda · Insecta · Odonata · Coenagrionidae · Enallagma
Accepted taxon. · checked 2026-07-15
the Palearctic from western Europe to eastern AsiaBroad range and selected reference localities — not a complete occurrence map.
the Palearctic from western Europe to eastern Asia
Ponds, lakes, canals and slow-flowing water with emergent vegetation.
Diurnal; adults fly mainly from late spring through summer.
Predatory: aquatic larvae take small freshwater animals and adults catch flying insects.
Solitary.
What makes this species remarkable?
Mature females occur in several colour forms, including a blue “male-like” morph thought to reduce persistent male harassment.
Its timetable changes with latitude: southern populations may complete development in one year, while northern larvae often require two.
Its mitochondrial genome is 16,661 base pairs long — among the largest odonate mitogenomes reported when it was sequenced.