At 2.5 to 3 mm this is the largest member of the genus. It is more or less unicoloured - a dark metallic blue, green or bronze. The elytra have 'shoulders'. The antennae are dark apically but segments 2, 3 and the apical part of 1 are paler. The legs are tawny brown but with darker femora.

Please provide a photograph and state the host plant species.

Habitats include anywhere the host, Iris pseudacorus (Yellow Iris), grows in abundance, usually in wetlands but also permanently damp soil in woodlands, parks, gardens etc..

Most likely to be seen from March or April, peaking in abundance from May to July and remaining common into the autumn.

Overwintered adults feed in the spring, consuming strips of epidermis parallel to the leaf margins and leaving conspicuous pale lines, before mating and ovipositing on the host foliage.

Common and often abundant throughout England and Wales, becoming scattered further north and scarce in Scotland although there are plenty of records from the west and Western Isles.

Occasional in Leicestershire and Rutland.