Unusual behavior of males of Aeshna cyanea (Odonata: Aeshnidae) to achieve a pairing 00

Abstract

Males of Aeshna cyanea employed specific behaviors to induce non-cooperative females into the mating position. Biting the female was used as a coercive behavior, thus showing a new function of biting in odonates. In two cases sitting females were caused to let go the substrate to which they latched on. A third female was bitten by a male after he had grasped her “incorrectly”, i.e. not from the dorsal but from the ventral side of her head. He turned her by means of the anal appendages into the “correct” tandem position and then attempted to achieve the mating position. In another case, a male tore a non-cooperative female off the egg-laying substrate and flew with her in many curves at a height of two to three meters. The female remained stiff and showed no cooperation. The male then flew to the open water of the pond and dropped her. Just above the water surface, the male grabbed her again. This time she cooperated and formed a mating wheel with him. These observations are discussed in the context of communication signals during forced mating attempts and a prospective model for the evolution of intimidation.

Keywords. Anisoptera, alternative reproductive behavior, biting, dragonfly, evolution, female defense, insect behavior, insect learning, sexual conflict, trade-off

Issue section: Original Article