Zircon Reed Beetle Donacia aquatica

The Zircon Reed Beetle, Donacia aquatica, is a small but visually spectacular leaf beetle belonging to the family Chrysomelidae, and the most threatened of Britain’s reed beetles. Adults are 6.7–8.8 mm in length and extraordinarily colourful – gold on the underside and thorax, with elytra bearing a broad, iridescent reddish-purple longitudinal band that shimmers through blue, green, and gold in different light, giving rise to the jewel-like common name. Adults are active between May and July, sitting on the leaves of emergent marginal vegetation, while larvae are entirely aquatic, feeding on submerged roots and rhizomes of sedges and related plants. The species has greatly declined, having been lost from over 80% of its UK range, and is now restricted to Inverness-shire and a few other sites in England. It is highly sensitive to eutrophication and habitat disturbance, making it a valuable indicator of water and habitat quality, and is listed as a UK Biodiversity Action Plan Priority Species and a Section 41 Conservation Priority Species in England. Image: © Udo Schmidt, Flickr.

Find out more: iNaturalist, UK Beetle recording, Buglife – Management factsheet