Phylogenetic systematics of the keratin-feeding genus Polynoncus Burmeister, 1876 (Coleoptera: Scarabaeoidea: Trogidae)

Abstract

Among the five known Trogidae genera, Polynoncus is the only one endemic to South America. Although the systematics within Trogidae is well established, the evolutionary relationships among Polynoncus species remain poorly understood. Here, we conducted a phylogenetic analysis based on maximum parsimony, using the equal and implicit weighting algorithm with all characters, in TNT v.1.5 software. The assembled data matrix consisted of 98 morphological characters scored for 48 taxa. Our results corroborate the monophyletic status of Polynoncus and its sister-group relationship with the genus Omorgus, both within Omorginae. In Polynoncus, three main lineages were recovered: (i) clade ‘pedestris’, with four species occurring mostly in the Andes; (ii) clade ‘pilularius’, whose species have been most reported in the temperate zone of South America; and (iii) clade ‘brevicollis’, whose species are distributed from the arid zones of Argentina and Chile to Peru, following through the Andes. This is the first species-level phylogeny presented for Trogidae.