Phylogeny of the Neotropical wood degrading beetles (Scarabaeoidea: Passalidae) of the tribe Passalini, inferred from molecular and morphological data

Passalini comprises 209 species divided into six genera. To date there is no published work that addresses the phylogenetic relationships among the genera of Passalini. Additionally, the monophyly of Passalus, the largest genus of the tribe (81% of its species) is contested. We performed a phylogenetic analysis based on morphological data and partial sequence of the 16S ribosomal subunit, to elucidate the relationships among the genera of Passalini, and test their monophyly. Of the genera for which we tested their monophyly, Passalus was the only genus found to be non-monophyletic, the same occurred for the subgenera Passalus (Passalus) and Passalus (Pertinax). The results indicated the subgenus Pertinax is divided into at least four distinct lineages, one of them corresponding to Rodocanthopus; thus, we propose the revalidation of Rhodocanthopus Kaup, 1869.