Violet oil beetle
Having had reported to me a couple of sightings of the violet oil beetle (Meloe violaceus) in April and May respectively (which I am very jealous about!), one in a garden and one in a pasture field, I thought I’d share a bit on this little beauty as they’re interesting guys - and not so little actually as far as beetles are concerned with the larger female growing up to 3 cm in length.
In his book Bringing Nature Home, Doug Tallamy has some amazing facts about beetles, he tells us that if diversity is a measure, beetles are far and away the most successful multicellular organisms alive today. There are over 300,000 named species of beetle, with likely many more to be named yet. That's only a little less than the estimated 320,000 world's plant species. There are six times as many described beetles as there are all vertebrates combined, 34 times more than birds. Astonishingly 30% of all animals are beetles!
The violet oil beetle is one of only four left of the eight oil beetles native to Britain. The other four have gone extinct, probably due to the lack of wildflower rich, semi-natural grasslands which have been in serious decline since the 1950’s mostly because of the change in agricultural methods. Their diet being lesser celandine (Ranunculus ficaria) and soft grasses.
The rugged oil beetle is rare and the short-necked oil beetle is very rare, the violet and black oil beetle are the most locally common, that’s not to say nationally common, of which none of them are. In fact, according to Buglife, only three sightings of the violet oil beetle have been made in the east side of Britain since the 1960’s. They are only really to be found in the South West, and the Peak and Lake districts.
In spring, the larvae climb out of the hole that the female beetle burrowed in may/June the previous year to lay her eggs, these ‘triungulins’ hitch a ride on a solitary bee’s back to the bees nest in which they proceed to eat the eggs of the host bee, the larvae grow and then go through another stage eating the pollen meant for the bees young before pupating and emerging as an adult the next spring, she then mates digs a burrow to lay her eggs and the whole process starts again.
Because of this, the violet oil beetle is an indicator of a good local solitary bee population and of high quality wildflower rich grasslands.
The oil part of the name refers to a noxious substance released from their knees if disturbed, allowing them to travel above ground in view of insect eating birds and without fear of being eaten.
If you have been lucky enough to have made a sighting of an oil beetle or in fact any unusual insect or plant, you can do your part as a citizen scientist by submitting a record of it on iRecord.
And/or send me pics of anything unusual in your garden as I’d love to know!
Image by Rezső Terbe from Pixabay
