Taxonomic Studies of the genus Decticus Serville, 1831 from China (Orthoptera: Tettigoniidae: Tettigoniinae), based on Morphology and Songs

Abstract

The genus Decticus Serville contains sixteen known species and subspecies, those widely distributed in the Palaearctic, among which three species and subspecies have been recorded in China. Morphological features in specimens of Decticus are variable. Stable characteristics and reliable methods for distict the species and subspcies are required. The geometric morphometrics was conducted to explore morphological variance on structure of right tegmen of Decticus specimens based on 30 landmarks, as well as qualitative analysis on variances of body size, male stridualtory apparatus and genital characters. The male calling songs structures, if available, can be compared and identified species usefully. The results indicate that the analyzed samples suggest two species, D. albifrons (Fabricius, 1775) and D. verrucivorus (Linnaeus, 1758). D. verrucivorus includes four subspecies, D. v. verrucivorus (Linnaeus, 1758), D. v. crassus Götz, 1970 (a newly recorded subspecies from China), and two new subspecies, D. v. latipennis ssp. n. and D. v. sayram ssp. n.. The songs of D. albifrons and D. v. verrucivorus, D. v. crassus are composed of numerous single chirps. One chirp of D. albifrons consists of one low-amplitude and short-duration syllable, and one high-amplitude and long-duration syllable. One chirp of D. v. verrucivorus consists of five syllables with different amplitudes. One chirp of D. v. crassus consists of five or six syllables with different amplitudes. Illustrations of necessary morphological and bioacoustical characters are presented.