Tishechkin D.Yu. 2019. Leafhoppers of the genus Macropsis Lewis, 1836 (Homoptera: Auchenorrhyncha: Cicadellidae: Macropsinae) on Sakhalin — different evolutionary trends in different species // Russian Entomol. J. Vol.28. No.2: 107–119 [in English].
Department of Entomology, Faculty of Biology, M.V. Lomonosov Moscow State University, Vorobyevy Gory, Moscow, 119234 Russia. E-mail: email@example.com
ABSTRACT. Illustrated descriptions of six species of the genus Macropsis from Sakhalin with data on host plants and male calling signals are given. For each species comparison with the mainland populations of the same or sister species is provided. Species studied demonstrate different evolutionary scenarios in insular populations. In M. fuscinervis, M. suspecta, and M. costalis no differences in any traits between the mainland and insular populations were revealed. In M. hinganensis the range of colour variability on Sakhalin is much wider than in the mainland. M. fuscula has two colour variations, the dark form occurs in the Western Palaearctic, and the light form in the Far East; Far Eastern specimens from the mainland and insular populations are indistinguishable in coloration. M. remota is undoubtedly an insular sister form of a widespread East Palaearctic M. flavida, but these forms distinctly differ in morphological traits and apparently, already reached the rank of good species. Thus, only in one of six forms insular isolation resulted in speciation. In all insular forms including M. remota calling signal patterns remained unchanged compared to the mainland populations. This proves that in geographically isolated forms, morphological divergence can occur without divergence of calling signal patterns. The number of species of Macropsis on Sakhalin is considerably less, than in the adjacent part of the mainland. Apparently, the cold climate is the main reason for the absence of some mainland species on Sakhalin; the impact of geographic isolation in this case is not so great.
KEY WORDS: Homoptera, Auchenorrhyncha, Cicadellidae, Macropsis, Sakhalin, insular populations, speciation, evolution.