Nomenclature of Tokyo cherry ( Cerasus × yedoensis 'Somei‐yoshino', Rosaceae) and allied interspecific hybrids based on recent advances in population genetics

The flowering cherries, Cerasus (≡Prunus subg. Cerasus; Rosaceae), including C. × yedoensis 'Somei‐yoshino', are popular ornamental trees in temperate regions of the world. Recent advances in molecular and population genetics have revealed that this group originated as an interspecific hybrid. We used these findings and the verification of type specimens to examine the nomenclature of nothotaxa including C. × yedoensis. Four nothotaxa, C. × yedoensis, C. × nudiflora , C. × sacra and C. × kashioensis, were confirmed to be hybrids resulting from crosses between C. itosakura and taxa of the C. serrulata complex (C. speciosa, C. sargentii, C. jamasakura and C. leveilleana, respectively). In addition, the hybrids found on Jeju Island are C. × nudiflora, a new combination for an interspecific hybrid shown to be genetically distinct from C. × yedoensis. A new nothospecies, C. × kashioensis is proposed for a hybrid between C. itosakura and C. leveilleana.