Meloe
Meloe violaceus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Coleoptera
Infraorder:	Cucujiformia
Family:	Meloidae
Subfamily:	Meloinae
Tribe:	Meloini
Genus:	Meloe Linnaeus, 1758
Species
See text
Synonyms
List Afromeloe Schmidt, 1913 Alveomeloe Pripisnova, 1986 Anchomeloe Iablokoff-Khnzorian, 1983 Chiromeloë Reitter, 1911 Cnestocera Thomson, 1859 Cnetocera Reitter, 1911 Coeloemeloe Coelomeloë Reitter, 1911 Desertimeloe Kaszab, 1964 Lampromeloe Reitter, 1911 Lasiomeloë Reitter, 1911 Listromeloë Reitter, 1911 Meioe Fuessly, 1775 Melittophagus Kirby & Spence, 1828 Meloedubius Meloegonius Reitter, 1911 Meloenellus Reitter, 1911 Melve Fischer de Waldheim, 1803 Micromeloë Reitter, 1911 Proscarabaeus Schrank, 1781 Submeloegonius Pliginskii, 1935 Taphromeloe Reitter, 1911 Trapezimeloe Pliginskii, 1935 Treiodous Dugès, 1869 Treiodus Triungulinus Dufour, 1828

Meloe is a genus of blister beetles commonly referred to as oil beetles.^[1] The name derives from their defensive strategy: when threatened by collectors or predators they release oily droplets of hemolymph from their joints (legs, neck, and antennae). This fluid is bright orange and contains cantharidin, a poisonous chemical compound. Wiping the chemical on skin can cause blistering and painful swelling of the skin. This defensive strategy is not exclusive to this genus; all meloids possess and exude cantharidin upon threat.

Morphology

Oil beetle adult dorsal view

Members of this genus typically have shortened elytra and lack functional wings. They are often iridescent blue, green, or black with pits/punctures on the elytra and thorax, and a bloated abdomen. Male antennae have kinks in some species which are shaped differently in different species.

Biology

As with all other members of Meloidae, the larval cycle is hypermetamorphic; the larva goes through several body types, the first of which is typically a mobile triungulin that finds and attaches to a host in order to gain access to the host's offspring. They usually climb onto a flower head, and await a bee there. They will then attach themselves to the bee. If it is a male, they wait for mating with a female. They will switch to the female when this takes place. If the bee is a female, however, she will take them back to her nest unwittingly. Once in the nest, the larvae morphs into a grub-like "couch potato" and feeds upon all of the provisions and the larva. Next, they form a pupa and emerge in various seasons depending on the species. Each species of Meloe may attack only a single species or genus of bees. Some are generalists. Though sometimes considered parasitoids, it appears that in general, the Meloe larva consumes the bee larva along with its provisions, and can often survive on the provisions alone; thus they do not truly qualify for this designation (see Parasitoid for definition).

Upon surfacing from their underground lives as larvae, the adults feed on plants in the Ranunculaceae, Ipomoaceae, and Solanaceae families. Meloe have appetites which are virtually insatiable.

Mating begins when a male mounts a female and releases chemical components through the kinks on the antennae, massaging her antennae and pulling them back. This serves to calm the female. Mating then occurs, with the male transferring his cantharidin to the female during this period and she coats her eggs with it. ^[2]

Species

The following species are recognised in the genus Meloe:^[3][4]

References

External links

• Media related to Meloe at Wikimedia Commons