A taxonomic outline of the Poecilimon affinis complex (Orthoptera) using the geometric morphometric approach

PeerJ. 2021 Dec 22:9:e12668. doi: 10.7717/peerj.12668. eCollection 2021.

Abstract

The genus Poecilimon contains 145 species, widely distributed in the Palaearctic, among which the Poecilimon ornatus group has the greatest diversity in the Balkans. Despite several revisions of the genus, the systematics of the species group, and in particular, of the taxa associated with the species Poecilimon affinis, is still unsolved. Due to morphological similarity, P. affinis with its subspecies, P. nonveilleri and P. pseudornatus form the Poecilimon affinis complex. The aim of this study is to test the hypotheses of an outlined species complex, namely the P. affinis complex, within the P. ornatus group using morphological data. Geometric analysis was conducted to explore variation in the structure of the male tegmen, ovipositor, male cercus, and male pronotum. The number of teeth and stridulatory file measurements provided additional information on morphological variation within the complex. A phylogenetic tree based on the cytochrome c oxidase subunit I gene (COI) was used for comparison with the morphological data. Canonical variate analysis showed that male tegmen and male cercus are good morphostructures to distinguish the taxa belonging to the P. affinis complex from other species in the P. ornatus group. This may confirm our assumption for the designation of the P. affinis complex. The results of the principal component analysis of stridulatory file measurements, molecular data, and CVA of the ovipositor suggest adding two additional species to the complex: P. ornatus and P. hoelzeli.

Keywords: Bush-crickets; Morphology; Phylogeny; Systematics.

Grants and funding

This work was supported by the National Science Fund (MES) of Bulgaria to Dragan Chobanov (DN11/14–18.12.2017) and a Bilateral Agreement between the Polish and Bulgarian Academies of Sciences (project: Convergent evolution of polyphyletic bush-crickets (Orthoptera: Phaneropterinae): micropterism and speciation). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.