Appearance
Size: 8-10mmBasic colour: Golden-bronze
Pattern colour: Elytra usually with variable reddish-purple patches and sides.

Habitat
On emergent vegetation, including reedbeds at the edges of various water-bodies and wetland/damp habitats.References:
Some text fragments are auto parsed from Wikipedia.
http://www.coleoptera.org.uk/species/donacia-marginata