Phylogeny of the Oxycoryninae sensu lato (Coleoptera:Belidae) and evolution of host-plant associations

Abstract

Phylogenetic relationships among the genera of the subfamily Oxycoryninae and other belids (Curculionoidea) were reconstructed by cladistic analysis using 21 terminals and 98 characters: 62 from imaginal morphology, 33 from larval morphology and three biological characters relating to host plants and larval feeding habits. Terminal taxa represent all extant genera of Oxycoryninae, two genera of each of the three tribes of Belinae plus two outgroup taxa used to root the tree. New information on the larvae and biology of the metrioxenines is used in phylogenetic reconstruction. In accord with the single optimal cladogram obtained, a revised classification of the Oxycoryninae is proposed. The subfamily is classified into three tribes (Oxycorynini, Metrioxenini and Aglycyderini), with the tribe Oxycorynini further classified into three subtribes (Oxycraspedina Marvaldi & Oberprieler, subtr. nov., Oxycorynina and Allocorynina) and the tribe Metrioxenini into two subtribes (Metrioxenina and Afrocorynina ( = Hispodini, syn. nov.)). Larval and adult unambiguous synapomorphies defining each clade are identified. Tracing the evolution of biological traits from the phylogenetic estimate indicates that drastic shifts to phylogenetically distant host plants occurred from the ancestral belid association with conifers. Structural, chemical and/or ecological similarities of the plant organs consumed apparently had a major influence in the colonisation of different plant taxa by this group of weevils.