Tandem grip mechanics and tandem linkage shifting in Odonata – reconstruction of evolution and phylogenetic significance


The functional morphology of the male caudal clasping apparatus of Zygoptera is compared to that of Epiophlebia superstes (Anisozygoptera) and Anisoptera. Hypotheses concerning the mechanics and muscle functions have been advanced by parallel construction of mechanical working models. The evolution of the clasping apparatus and the tandem linkage shifting – from the female pronotum to the head – in the stem group of the Anisozygoptera + Anisoptera (Neoconjuncta) is reconstructed, beginning with a system, which in essential characters resembles that of Epallage fatime (Euphaeidae). New acquisitions of the Neoconjuncta, Anisozygoptera and Anisoptera are described and interpreted. An interdependent evolution of the clasping apparatus + tandem linkage and the flight apparatus is discussed. Characters of both systems in the Euphaeidae and the Neoconjuncta are evaluated as synapomorphies, establishing a group Heteronoda. The Zygoptera are substantiated as a paraphyletic group. The functional morphology of the motion system of the cereal and epiproctal filaments of the Ephemeroptera has been studied for comparison. It shows strongly autapomorphous features, adapted to the display flight.

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