Species of the day: Thick-legged Flower Beetle

, 15 May 2020
Species of the day: Thick-legged Flower Beetle
Thick-legged Flower Beetle © James Duncan

By James Duncan

Learning & Engagement Officer

The Beetles belong to a simply gigantic group of insects that form the Order Coleoptera. Not only do they make up around 40% of all 'described' insects, they represent approximately a quarter of all currently classified lifeforms on Earth. Of course, it's estimated there are actually five to six times more species across the globe than are currently described, though that doesn't detract from the fact they constitute a staggering volume of biomass. Beetles are ultimately the most dominant, species-rich terrestrial organisms on the planet, fulfilling a huge variety of pivotal ecological roles. Just one of these is the Thick-legged Flower Beetle (Oedemera nobilis) which also goes by a number of other common names, including the 'Swollen-thighed Beetle' and 'False Oil Beetle.' Adult beetles can be distinguished from other insects by their tough, hardened forewings, known as elytra, which essentially give them a form of 'armour plating', covering the membranous hind wings. The word Coleoptera in fact derives from Greek words meaning 'sheath wing.' All beetles have biting mouthparts and the word 'beetle' likely stems from the Old English 'to bite.' Their biting mouth-parts enable them to feed on an immense diversity of food-sources, ranging from plant and fungal matter to an assortment of other animals. 

The naming of the Thick-legged Beetle comes by virtue of the male's swollen femora (hind legs). This is a species that appears to have been putting serious time in at the gym, though the females don't exhibit this trait as they're a sexually dimorphic species. Another distinctive feature is owing to their long, thin elytra which don't quite meet at the base, leaving the underwings slightly exposed. It really is a beautifully eye-catching iridescent green beetle, though it may sometimes exhibit a coppery sheen, particularly so in the female's case. It seems decidedly appropriate that its species name of nobilis (noble) seems almost to reflect the magnificent grandeur of its sparkling armour. The family to which this beetle belongs, the Oedemeridae, are sometimes also known as the 'False Blister Beetles', owing to a resemblance to the true 'Blister Beetles' which contain a blistering chemical known as cantharidin. It seems that some family members may in fact contain cantharidin, traditionally used as an aphrodisiac, though also used for the treatment of warts. They may also have anti-tumour properties that inhibit the growth of cancerous cells.

This is the perfect time to spot a Thick-legged Flower Beetle, which will typically be seen crawling amongst flowers, for its diet is made up of pollen. They seem to display a strong preference for large open-flowered species, from families such as Asteraceae (composites), Apiaceae (umbellifers) and Rosaceae (roses), though perhaps the number one species to find them on is the Oxeye Daisy (Leucanthemum vulgare). They're a widely distributed species across western lowland Europe and the Mediterranean and are now expanding their range northwards through Britain, having once only been common in the south. Like us, they've a lover of the sun and bright hot days offer the best opportunity to spot their dazzling colours. Though more typically a creature of meadows and grassland, they're increasingly being found in parks and gardens that offer the appropriate pollen sources. Being a species that spend its time relentlessly moving between flowers, the Thick-legged Beetle is also a rather wonderful generalist pollinator.   

Thick legged Beetle © Derek Middleton

Thick-legged Flower Beetle © Derek Middleton

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Comments

  • Roger musselle:

    2019 was a very good year in our Woodingdean garden for the beautiful thick legged flower beetle. In the past we have only seen individuals but spotted them on several occasions between June14th &June28th on bramble in flower with a maximum of 25 on the same bush in the sunshine on the 27th.

    16 May 2020 16:12:00

  • Many thanks for these details. I have been able to identify the beautiful insect I found in my garden in Somerset today.

    07 Jun 2020 15:54:00

  • Sheila Stubbs:

    My daughter in Kent took a pic of one of those beetles today and she and the children were quite fascinated by it. I managed to identify it for them but living in Scotland I have never seen one.

    07 Jun 2020 19:40:00

  • Lisa Spowart:

    I saw two today in my garden (Gosport in Hampshire) very lovely to look at. Never seen one before and just moved down here from the North East which is possibly why! 😉

    09 Jun 2020 00:15:00

  • Sam:

    Im in the west mids and saw one of these drowning in the dog bowl today. Gave him a little scoop!

    23 Jun 2021 17:11:00

  • Sam:

    Im in the west mids and saw one of these drowning in the dog bowl today. Gave him a little scoop!

    23 Jun 2021 18:59:00

  • Jan:

    Saw one today in North London amongst the bramble flowers in my allotments. Never seen one before.

    05 Jul 2021 17:26:00

  • Victoria:

    Found a lovely little one of these today on my ox eye daisies. Sitting next to a small fly and a bee.

    12 Jul 2021 21:55:00

  • Claire:

    I have found on in my porch in Solihull today. Now I know what it is I will find a suitable flower for him.

    03 Jun 2022 18:16:00

  • Sue Read:

    This beautiful little beetle landed in my hair this morning. So pleased to have identified him. Thank you. I live in rural Suffolk . June 9th 2022

    09 Jun 2022 12:47:00