First Molecular Phylogeny Estimate of the Weevil Tribe Mecopini (Curculionidae: Conoderinae) Unveils its Polyphyletic Nature at the Tribal and Generic Level.

Abstract

Mecopini has received limited attention since the last century, highlighting an important knowledge gap in its systematics and taxonomy. The morphological characteristics of several genera within this tribe contradict the widely accepted tribal diagnosis, suggesting the current classification is unsustainable. In this study, we examined mecopine specimens from Taiwan and the Philippines, reconstructed the first molecular phylogeny estimate for this obscure tribe, and examined type series of all described Pempheres Pascoe, Chirozetes (Chirozetes) arotes Heller and Chirozetes (Mesochirozetes) formosanus Heller, representing two subgenera within the genus Chirozetes Pascoe, to propose taxonomic acts on these genera. Our results reveal the polyphyletic relationships within Mecopini at both the tribal and generic levels. Based on the phylogenetic framework and morphological characters, we propose excluding Agametis Pascoe from this tribe and elevating the subgenus Mesochirozetes Heller to full generic status. We also designate lectotypes of Mesochirozetes formosanus Heller and two Pempheres species. Our study highlights the uncertainties of current classification of Mecopini, raising questions not only about the tribal composition but also the monophyly of genera within this tribe. Further studies are necessary to address these systematic issues, which may prompt a reevaluation and redefinition of this little-known tribe.