Eva K. Putri, Ben Wielstra, Kasper P. Hendriks, Peter C. van Welzen, Roderick W. Bouman, Ryan F.A. Brewer, Sylvia M. de Oliveira
Kirganelia (Phyllanthaceae) is a palaeotropical genus recently reinstated as separate from Phyllanthus, yet species boundaries remain unclear, especially within the widespread and morphologically variable K. reticulata complex. To resolve this, we generated Angiosperms353-based phylogenomic data from 233 samples and applied an integrative framework combining maximum likelihood and coalescent-based trees, ADMIXTURE analysis, phylogenetic networks (PhyloNet, SplitsTree), and diagnostic traits. These approaches consistently supported three main lineages and justified the recognition of 30 clades of individuals, here hypothesized to represent species. One lineage—including K. zippeliana, K. glaucina, four undescribed taxa, and Moeroris retinervis—is sufficiently distinct to be treated as a new section within Kirganelia, with nomenclatural changes to follow. Within the K. reticulata complex, we recognize five species: two from Africa (K. polysperma and a yet unpublished species), and three non-African species (K. baccata, K. microcarpa, K. reticulata). Network analyses revealed hybrid ancestry in multiple taxa, particularly within the “Malagasy” clade, highlighting reticulate evolution as a key driver of morphological overlap and phylogenetic discordance. These findings demonstrate the limitations of relying solely on monophyly for species delimitation in recently diverged lineages and support using multiple lines of evidence to define coherent evolutionary units. This work provides an evolutionary foundation for future studies of Kirganelia taxonomy, diversity, and biogeography. © 2026 The Author(s). TAXON published by John Wiley & Sons Ltd on behalf of International Association for Plant Taxonomy.
Naturalis Biodiversity Center, Darwinweg 2, Leiden, 2333 CR, Netherlands; Institute of Biology Leiden, Leiden University, Sylviusweg 72, Leiden, 2333 BE, Netherlands; Universitas Negeri Surabaya, Jalan Lidah Wetan, Lidah Wetan, Surabaya, 60213, Indonesia; Department of Biology, Botany, University of Osnabrück, Barbarastraße 11, Osnabrück, 49076, Germany; Hortus Botanicus Leiden, Leiden University, P.O. Box 9500, Leiden, 2300 RA, Netherlands; Groningen Institute for Evolutionary Life Sciences, University of Groningen, Nijenborgh 7, Groningen, 9747 AG, Netherlands
