Tishechkin D.Yu. 2019. Calling signal pattern vs. genitalia morphology in Planaphrodes Hamilton, 1975 (Homoptera: Auchenorrhyncha: Cicadellidae: Aphrodinae) — which trait evolves faster? // Russian Entomol. J. Vol.28. No.3: 227–232 [in English].
Department of Entomology, Faculty of Biology, M.V. Lomonosov Moscow State University, Vorobyevy Gory, Moscow 119234, Russia. E-mail: firstname.lastname@example.org
ABSTRACT. Male calling signals and genitalia of four species of Planaphrodes were investigated. In P. laevus and P. elongatus, penis stem is slender with two pairs of processes in the middle part, whereas in P. bifasciatus and P. monticola it is wide in lateral view with three pairs of processes; the level of interspecific morphological differences within each pair of species is approximately the same. However, in P. laevus and P. elongatus, signal patterns are distinctly different and share only one similar component, whereas in P. bifasciatus and P. monticola signals are almost identical. Convergent origin of such an elaborate signal patterns in last two species is hardly possible. The more probable alternative is a subdivision of the range of the ancestral form in two parts which resulted in morphological divergence, whereas signal patterns in both forms remained unchanged. Thus, in some cases morphological traits can evolve faster than the acoustic signal pattern; examples of signal similarity in other taxa of leafhoppers and grasshoppers confirm this hypothesis.
KEY WORDS: Homoptera, Auchenorrhyncha, Cicadellidae, Planaphrodes, calling signals, morphology, evolution.