<i>Khaya</i> revisited: Genetic markers and morphological analysis reveal six species in the widespread taxon <i>K. anthotheca</i>

Khaya (Meliaceae) is a widespread genus of trees distributed from the tropical forests Africa to Madagascar and Comoros. species are very close morphologically some contain considerable phenotypic ecological diversity, raising question their delimitation: this case anthotheca s.l. (sensu lato, including K. nyasica), which often lumped with grandifoliola ivorensis. We tested delimitation within by combining population-genetic morphological data. First, visual inspection over thousand specimens suggested existence five morphogroups. Second, after genotyping 498 samples at 71 nuclear SNPs, Bayesian clustering analyses (STRUCTURE) first identified genetic clusters (K1–K5), while further subdivided K5 into two clusters. The six obtained in parapatry or allopatry West East Africa, except for cluster K4, sympatry K3 Central Africa. partitioning also largely congruent morphogroups identified. differentiation these was confirmed statistical 27 leaf characters. clear-cut between clusters, few admixed genotypes even contact zones, argues recognition distinct following biological concept. Our highlight that current taxonomic treatment underestimates one-half total number species. identify new species, circumscribe support rehabilitation rank three taxa considered be synonyms (K. agboensis, euryphylla, nyasica). These results illustrate strength data delineate an African rainforest tree complex.