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Beetles and humans

includes several hundred species worldwide,

such as the Afrotropical Nairobi Eye Fly Paederus

eximius. These brightly colored flying insects are

attracted to light and may enter houses as a result.

They are also called “dragon bugs” because of

their bright colors and the burning sensation that

they cause on contact with the skin. The active

ingredient in this case is not cantharidin but a

similar chemical, pederin, which is extremely

rare in nature (apart from these beetles it is only

known from some marine sponges) and is under

investigation as a potential anticancer drug.

Other drugs derived from insects are also

under investigation. The light-producing enzyme

luciferase and associated genes, used in various

Elateroidea, such as fireflies, for mating signals

or in defense, have been applied medically for

monitoring the progress of infections or to

visualize, for example, liver cells in human

embryonic development. Some beetles such

as the Yellow Mealworm Tenebrio molitor

(Tenebrionidae), because they can be bred in

enormous numbers—up to several tons per day

MEDICINE

Compared to many groups of insects—such as

Hymenoptera (ants, bees, and wasps) that can bite

and sting, and Diptera (true flies), which include

vectors of important diseases, such as malaria and

yellow fever carried by mosquitoes—beetles are

relatively innocuous from a medical and human

health point of view. Blistering of human skin can

be caused by exposure to the cantharidin secreted

by several beetles of the families Meloidae and

Oedemeridae, the former often called “blister

beetles” and the latter, in parts of Oceania,

“bubble bugs” because of the circular, liquid-filled

blisters they can cause, for example if accidentally

crushed against the skin. The merits of the

Spanish Fly Lytta vesicatoria (Meloidae), a green

beetle from southern Europe, as an aphrodisiac

has been discussed for centuries, including by the

notorious Marquis de Sade (1740–1814)—whose

name is the origin of the word “sadist”—but it is,

in fact, a deadly and painful poison.

Blisters can also be caused by exposure to

some Staphylinidae of the genus Paederus, which