Quantitative assessments and taxonomic revision of the genus Archirhagio with a new species from Daohugou, China (Diptera: Archisargidae)

Abstract

A new species, Archirhagio gracilentus sp.n., is described from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia in China. The ground plan of genital structures of Archirhagio is described according to the well-preserved male and female genitalia in this new species. Based on venational patterns of five species of the Archirhagio, we conducted the geometric morphometric analysis to quantitatively review and revise the taxonomy of Archirhagio. The results indicate that most species of the genus, with one exception, have distinctive interspecific variances to support their taxonomy. Therefore, we propose Archirhagio mostovskii as a new synonym for Archirhagio zhangi according to both morphological characters and quantitative analyses. Furthermore, a traditional key character, the position of m-cu, is too unstable to be used as a specific diagnosis. A key to all species of the Archirhagio is also provided. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:112F5E51-42AB-4438-9512-32E19E1CF5E3.