Phylogenomic analyses of thePhotiniacomplex support the recognition of a new genusPhippsiomelesand the resurrection of a redefinedStranvaesiain Maleae (Rosaceae)

Abstract

AbstractPhotiniaand its morphologically similar allies in Maleae (Rosaceae) consist of five currently recognized genera:Aronia, Heteromeles, Photinia, Pourthiaea, andStranvaesia, and 68 species, distributed in Asia and North and Central America. Despite previous efforts to clarify relationships in this group, the generic delimitations have remained uncertain. Our goals were to reconstruct a robust phylogeny ofPhotiniaand its close allies to test the monophyly of the currently recognized genera, especiallyPhotiniaandStranvaesia, and the hybrid origin hypothesis ofPhotinia bodinieri. This study employs complete plastomes and the entire nuclear ribosomal DNA (nrDNA) repeats assembled from the genome skimming approach with a broad taxon sampling of 81 species in 30 genera of Rosaceae, especially Maleae. Based on three datasets, including the whole plastome, coding sequence, and nrDNA repeats, the results of maximum likelihood and Bayesian inference analyses showed that the previously circumscribedStranvaesiaandPhotiniawere each non‐monophyletic. Six clades have been recovered herein withinPhotiniaand its allied genera:Aronia, Heteromeles, Photinias.s.,Pourthiaea, Stranvaesia, and a new genusPhippsiomelesconsisting of the Central American species formerly placed inPhotinia. The strong conflicts between the plastome and nrDNA phylogenies ofPhippsiomelesandStranvaesia tomentosasuggest the possibility that they may have each originated involving hybridization events, while no incongruence among datasets was detected to support the hybrid origin ofPhotinia bodinieri. We provide 12 new combinations, to transfer eight taxa of the New WorldPhotiniaintoPhippsiomelesand clarify the generic placements of several species ofPhotiniaandStranvaesia.