Pythiopina, an enigmatic subtribe of darkling beetles (Coleoptera: Tenebrionidae: Pedinini): taxonomic revision, microtomography, ecological niche models and phylogenetic position

Abstract

Morphological, anatomical, and distributional data concerning the South African endemic beetle subtribe Pythiopina (Tenebrionidae: Pedinini) are revised. Five species, representing two genera, are recognized. Included in this total is one new species (Meglyphus mariae Kamiński sp.n.). The following species are placed in synonymy: Meglyphus ciliatipes [=Meglyphus calitzensis syn.n.]; Meglyphus laenoides [=Meglyphus andreaei syn.n.; =Meglyphus namaqua syn.n.]. Microtomographic models for all valid Pythiopina species, including the holotype of the newly described species, are presented and analysed. Endoskeleton morphology (specifically characters of the tentorium and metendosternite) proved to be informative at the specific and generic levels. An identification key is provided to all known species of the subtribe. Environmental niche models are presented for the majority of species. A molecular phylogeny of Pedinini based on six genetic loci (28S: D1–D3 region; 28S: D4–D5 region, COII, ArgK, CAD2, wg) was also produced to explore the phylogenetic position of Pythiopina. This analysis is the first to include representatives of all seven subtribes of Pedinini, and supports a sister relationship between Pythiopina and the Palaearctic subtribe Dendarina. Results also suggest the existence of a second pair of sister taxa within Pedinini (in addition to Melambiina) with an amphitropical African distribution. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:285AD87A-46B1-4FE9-BC57-949EA1F70D49.