New PDF release: Idiomactive English

By Teophil Vera

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VENOM APPARATUS OF BEES, WASPS, ANTS, CATERPILLARS 17 Myrmicinae (Foerster, 1912)* also have well-developed stings. In the latter subfamily, however, many genera with sting apparatus reductions are found. Their sting parts are relatively smaller and partly reduced and these genera can no longer sting. The Dorylinae possess more or less atrophied stings (Foerster, 1912; Stumper, 1960). They are still more reduced in the Dolichoderinae. In this subfamily tiny sting organs exist. Here, as in some Myrmicinae genera, the oblong and quadrate plates are reduced with exception of their thickened margins.

By contraction of the venom reservoir muscles the secretion is injected into the victim. Schlusche (1936) could not find any locking apparatus in the wasp sting. Such a formation seems unnecessary, because in contrast to the pump sting type, stinging movements and venom emptying are separate. We should also mention how the venom is given off in the camponotines, which have a well-devèloped venom gland but no functioning sting (Forel, 1878). The very weak wall muscles of the reservoir are not able to eject the venom.

The sting loss is no accident but a natural reaction developed by selection, an autotomy. It is directed against the largest enemies of the honeybee, against honey- and brood-robbing mammals and birds. The following facts demonstrate this. As already mentioned (see Table II), the sting apparatus of the honeybee worker possesses a series of peculiarities in comparison to the more primitive queen bee sting and to those of solitary bees. The sting possesses a preformed breaking point: the spiracular plates and muscles which in the queen bee prevent the loss of the sting are reduced strongly in the worker.

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Idiomactive English by Teophil Vera


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