Osmeterium
The Osmaterium neck is a fork that sits between the head and the first thoracic segment of the caterpillars of moths Knight ( Papilionidae ). It is used to deter predators. There is everted at risk by forcing Hämolymphflüssigkeit. In addition, the caterpillar bends the front part of the body upwards to act menacing. In addition to the usually yellow, orange or reddish color and the peculiar, thick - fleshy form, the enemies confused, sends the caterpillar with sitting on that organ glands a foul-smelling secretion from, which causes enemies such as ants escape. This aroma is generated by terpenes, whose composition is different depending on the type. If the bead several times disturbed and they noticed that their response does not succeed, she flees. In normal condition, the Osmaterium is collapsed and not visible.