Molecular phylogeny of Pedinini (Coleoptera, Tenebrionidae) and its implications for higher-level classification

Abstract

The first comprehensive molecular phylogeny of the darkling beetle tribe Pedinini is inferred from analyses of DNA sequence data from the following six loci: 12S rRNA, 28S rRNA, cytochrome c oxidase subunit II (COII), wingless (wg), CAD/rudimentary (CAD2) and arginine kinase (ArgK). Bayesian and maximum likelihood analyses were performed for a dataset of 79 species, representing all seven pedinoid subtribes. Low-coverage genome sequencing methods were used to obtain sequences from pinned historical specimens representing taxa crucial for the phylogeny. The results reveal that Pedinini is paraphyletic with regard to Helopinini. In contrast, monophyly of the majority of the subtribes (except Melambiina) is supported. Three main clades are recovered: 'Dendaroid' (Dendarina and Melambiina), 'Pedinoid' (Helopinini, Leichenina and Pedinina) and 'Platynotoid' (Eurynotina and Platynotina). Phylogenetically important characters defining these clades are documented, and their relevance/validity in phylogenetic studies is discussed. A new tribal-level classification is proposed. In order to restore the monophyly of Pedinini, Helopinini is included as a subtribe, and the names of the previously designated Helopinini subtribes are synonymized with the nominal one. Pythiopina is synonymized with Dendarina. The genus Ostorius is considered as a synonym of Adelonia. An identification key to the revised Pedinini subtribes is provided.