Meloid beetle

Defensive Compounds. Clerid beetles such as Trichodes apiarius were found to contain considerable amounts of cantharidin 48, accompanied by small to minute amounts of palasonin 49 [ 122,265]. Previously, the latter has been known only from seeds and fruits of the Indian shrub, Butea frondosa (Leguminaceae). It is suggested that these predatory beetles feed on cantharidin producing oede-merid and meloid beetles, see below. Several clerid species are canthariphilous [266,267],... 

Defensive Compounds. Apart from cantharidin 48 and palasonin 49 the corresponding non-toxic imides cantharidinimide 159 and palasoninimide 160 could be identified in various bodyparts of the meloid beetle, Hycleus lunata [310,311]. 

Several predation tests especially with spiders and blister beetles [121,313, 314], show that spiders exhibit a wide range of sensitivities to meloid beetles as prey. In the racoon Procyon lotor it was shown that they quickly form an aversion to blister beetle prey, which is induced by cantharidin [314]. 

A number of symbioses exist in which insects use natural products to parasitize insect colonies. Meloid beetles, which contain cantharidin (142) (Scheme 17) as a blistering repellant, spend one part of their complicated life cycle in nests of hymenopterans. The first larval stage is the mobile triungulin form. In yHf/of and other genera, these larvae climb flowers and assemble to form multispecimen aggregates with bee-like appearance and an attractive effect on male bees. In Mdoe franciscanus, the parasite of the solitary bee Habropoda pallida, it has been... 

McCormick, J. P. and J. E. Carrel, Cantharidin biosynthesis and function in meloid beetles, in Pheromone Biochemistry (G. D. Prestwich and G. J. Blomquist, eds.), 307-350, Academic Press, Orlando, FL, 1987. 

Synthesized in the meloid beetle Lytta vesicatoria present in the blood, released by reflex bleeding from joints, feeding deterrent... 

A wide variety of defense substances occur in insects. They are either accumulated simply in the insect s body, like the cardiac glycoside calotropin in the monarch butterfly, or they are constituents of the hemolymph and are discharged, e.g., by reflex bleeding, when a predator attacks the insect, as with cantharidin from the meloid beetle. In some cases the products may be actively expelled. A characteristic example in this respect is the ejection of quinones from special glands of the bombardier beetles Brachynus sp.) (Fig. 338). 

Some mono- and sesquiterpenoids are also found in animals. The most prominent examples are defensive secretion of insects. Iridoids are present in various beetles and cantharidin, a monoterpene derivative with skin irritating properties, in meloid beetles. Bitter tasting iridoid glycosides are found in some caterpillars. Also, the toxins of termites contain mono- and sesquiterpenes [9]. 

Cantharidin is a defensive secretion of meloid beetles (another type of blister beetle, Plate 10). It forms about 0.25-0.5% of the body weight, and is stored in the haemolymph and male genitalia. It is present in all life... 

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