Re-evaluation of the genus Phonochorion (Orthoptera: Tettigoniidae: Phaneropterinae)

Phonochorion Uvarov (Orthoptera: Tettigoniidae: Phaneropterinae) is a little known genus consisting of three species: Ph. satunini, Ph. artvinensis and Ph. uvarovi. The objective of this study is to conduct a thorough distributional, taxonomic and systematic revision of the genus Phonochorion using both bioacustic and external morphological characters. Field surveys indicate that the genus is distributed from the Trabzon region of Turkey to the Khulo province of Georgia however the exact limit of the eastern distribution of the genus remains unknown. Phonochorion species occur only on the northern slopes of the East Black Sea and Lesser Caucasus Mountains. The Coruh Valley, which seprates the East Black Sea and Lesser Caucasus Mountain ranges, seems to be an effective physical and climatic barrier and determines the distribution of these species. Ph. uvarovi can clearly be distinguished from Ph. satunini and Ph. artvinensis by the calling songs of males and external morphological characters. Ph. artvinensis and Ph. satunini differ in several taxonomic characters but the males have virtually identical calling songs. From a character evolution perspective, although geographically more distant, Ph. satunini is more closely related to Ph. uvarovi than Ph. artvinensis. Morphological similarities in several characters indicate Phonochorion to be most closely related to Polysarcus zacharovi and the Poecilimon heroicus-group. Within the genus Phonochorion, song structure and morphological characters clearly indicate Ph. uvarovi to be the basal taxon.