Meloe violaceus

Life-forms

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Protostomia
Cladus: Ecdysozoa
Cladus: Panarthropoda
Phylum: Arthropoda
Subphylum: Hexapoda
Classis: Insecta
Cladus: Dicondylia
Subclassis: Pterygota
Cladus: Metapterygota
Infraclassis: Neoptera
Cladus: Eumetabola
Cladus: Endopterygota
Superordo: Coleopterida
Ordo: Coleoptera
Subordo: Polyphaga
Infraordo: Cucujiformia
Superfamilia: Tenebrionoidea

Familia: Meloidae
Subfamilia: Meloinae
Tribus: Meloini
Genus: Meloe
Subgenus: Meloe (Meloe)
Species: Meloe violaceus
Name

Meloe violaceus Marsham, 1802
References

Meloe violaceus Marsham, 1802

Vernacular names
suomi: Sinitoukohärkä

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.

Meloe violaceus – Lateral view

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.
References

Anderson, R., Nash, R. & O'Connor, J. P., 1997, Irish Coleoptera: a revised and annotated list, Irish Naturalists' Journal Special Entomological Supplement, 1–81
Buck, F. D., 1954, Coleoptera: Lagriidae to Meloidae
Bug Guide, Oil Beetles (Meloe)
Buglife - The Invertebrate Conservation Trust, Join the Hunt for Amazing Oil Beetles
Buglife - The Invertebrate Conservation Trust, Oil Beetle Life Cycle
Funet
Meloidae