Look out for the sparkling copper-green of the Swollen-thighed Beetle on flowerheads on hot sunny summer days. 
Photo: Amanda Scott

Scientific name: Oedemera nobilis

Other common names: Thick-legged Flower Beetle, False Oil Beetle

What to look for:

• Colouring and other features: Bright coppery green iridescent beetle, distinguished by the elytra (the hardened modified forewings) being thin and slightly separated, and also by the swollen hind femora (upper back legs) of the males.
• Size: Length, 8 to 10 mm.
• When: Can be seen from April to August, usually on flowerheads, particularly in bright sunshine.
• Where: Common in southern England and as far as the midlands and North Wales, but less common in northern England and Scotland.

Peer among umbellifer species and Ox-eye Daisies in the summer, and you stand a good chance of seeing the very aptly named Swollen-thighed Beetle. It is only the male of this species that has the very obvious swollen hind femora (the upper part of its back legs). Particularly active on hot and sunny days, the Swollen-thighed Beetle feeds on pollen and so is easy to spot, its iridescent coppery green hue contrasting strikingly with the more delicate flower colouring.

Did you know…?

…The larvae of the Swollen-thighed Beetle live and feed inside the dried stems of various herbaceous plants.

More information and references:

Chinery, M., 2004. Collins Complete Guide to British Insects. Collins, London.

Jones, S., 2010. Insects of Cornwall and the Isles of Scilly. Alison Hodge, Penzance.

Published: June 2015
Author: Amanda Scott
Photos: Amanda Scott