Buglife If you go down to the woodland glade, you might be lucky enough to see a Violet oil beetle (Meloe violaceus). They began their emergence in March and will soon peak in numbers making April the perfect time to find one of these iridescent insects.
Of the four remaining species of British oil beetle, the Violet oil beetle has the most varied habitat preferences and can be found in woodland edge habitats, glades and rides, upland moorlands and on flower-rich grasslands.
Violet oil beetles have a striking appearance despite their underlying black coloration, as light is refracted off their lustrous carapace to give them a purple, blue or green sheen. When they first emerge as adults, their abdomen is small and compact but, as they gorge themselves on lesser celandine (Ranunculus ficaria) and soft grasses, their abdomen becomes distended and can extend some way beyond the tip of their wings. They can often be found sunning themselves on paths and females are sometimes seen digging burrows in patches of bare ground, in which they lay their eggs.
Juvenile Violet oil beetles are tiny, black, louse-like creatures that emerge in spring and lie in wait on flowers for solitary mining bees that visit the flowers to collect nectar and pollen. The triungulins take advantage of the mining bees, firstly by hitching a lift on their back, and again in the bees’ nest, by eating the food so diligently collected by the bee for its own young; the beetle equivalent of a cuckoo. Despite their coercive nature, Violet oil beetles are important for conservation as they are indicators of strong mining bee populations and of high quality, wildflower-rich habitats.
https://www.buglife.org.uk/bugs/bug-directory/violet-oil-beetle/
Devonshire Association Entomology Section The Entomology Section promotes the study and recording of insects and also spiders in the county.
Meetings, talks, exhibitions, publications and field trips are arranged annually across the county of Devon and are suitable for beginners and experienced alike. Field trips are usually held in association with other specialist groups with whom we maintain close links. We also meet with other sections to demonstrate, and learn, about the inter-relationships with other disciplines.
With at least ten specialists in different Orders within the insect class we cater for a wide range of interests. Some of our Recorders are national experts in their field and hence we are the major collective source of entomological expertise in the county.
https://devonassoc.org.uk/organisation/sections/entomology-section/
Devon Biodiversity Record Centre Submit your sightings of Violet Oil Beetles and other species in Devon
https://www.dbrc.org.uk/wildlife-sightings/
Violet Oil Beetle, field on the Ridge and Valley Walk east of Homeland Bridge, Chawleigh, photo by Grant Sherman 10th May 2021
National Biodiveristy Network The NBN Atlas is a collaborative project that aggregates biodiversity data from multiple sources and makes it available and usable online. It is the UK’s largest collection of freely available biodiversity data.
https://species.nbnatlas.org/species/NBNSYS0000024952
Wikipedia Meloe violaceus, the violet oil beetle, is a species of oil beetle belonging to the family Meloidae subfamily Meloinae. These beetles are present in most of Europe, in the eastern Palearctic realm, in the Near East, and in North Africa.
This species is characterized by hypermetamorphosis, a kind of complete insect metamorphosis in which, in addition to the normal stages of larva, nymph and imago, they have several others, with great differences in appearance and way of life. The body of Meloe violaceus is 10–30 millimetres (0.4–1.2 in) long, females are somewhat larger than the males. These beetle are black-blue or violet-blue, head and pronotum are very finely dotted and the elytra are quite shorter than the abdomen, as in other Meloinae species.
The adults live on a sunny, dry area with flowering plants, feeding on pollen. In May–June the female digs into the soil 20–30 millimetres (0.8–1.2 in) deep cylindrical holes, where they lay a very large quantity of eggs (about 2,000–10,000). After about a month larvae emerge from eggs and climb up on grass or on flowers, waiting to cling to the thorax of approaching potential host insects seeking pollen or nectar. The larvae have an exclusively parasitic life, primarily in the nests of solitary bees, or sometimes of locusts. If the larvae have inadvertently selected a honey bee, they die in the hive and may cause serious damage.
When the host female bee lays eggs in its cells, the first-stage larva of the violet oil beetle eats the eggs of the bee, increases in volume and becomes the second-stage larva, which continues its development eating honey and pollen. The larva, after other two stages, forms the nymph and finally the imago.
