Natural History Photographs

Meloidae is a family of beetles, known as Blister beetles, so called for their defensive secretion of a blistering agent, cantharidin. Many of them are aposematically colored, announcing their toxicity to would-be predators. Larvae of most genera enter the nests of wild bees and live on the bee larva and its provision; they thus can be considered kleptoparasites. An example is the Oil beetle, Meloe proscarabaeus. In spring females dig a hole, in which they lay a large number of eggs. When the eggs hatch, so-called triungulin larvae emerge, which climb into flowers. If the flower is visited by a bee, a larva climbs on the bee. Only if the bee is a female, the larvae is transported to the nest of the bee, where they leave the bee and wait till the nest is finished. They then kill the bee egg and start feeding on the food that was provided by the bee. They must consume the stored pollen of several nests, since the grown-up beetle is far larger than their host.
Meloe proscarabaeus
Epen, the Netherlands; 17 April 2013.
Bombus cf. zonatus carrying triungulin larvae
Kavacik (Burdur), Turkey; 11 June 2012.
This Bumble bee carried triungulin larvae, one of which is visible in the last yellow band near the tip of the abdomen, and one in the orange-yellow hairs between the wings. The triungulin larvae are of a darker orange color. They are unable to recognize a proper host, and thus these might well have jumped on the wrong horse...