A new species from Turkey, Sorbus erzincanica (Rosaceae); inference from genomic data and morphometry

Sorbus has an extensive speciation in Turkey and among its species, an unusually distinctive population was discovered in the Irano-Turanian phytogeographical region. Specimens of the population are closely related to S. aucuparia with several important distinctive characteristics: the outline of the leaves, shape of terminal leaflets, numbers of flowers, fruits per infructescence, fruit size and genome size. Based on the distinguishing morphological characters and the genomic data, the population is described as a new species with the name Sorbus erzincanica. Measurements of the nuclear DNA content of the proposed new species, closely related taxa (S. aucuparia, S. roopiana) and the other Sorbus species which occur in the same habitat (S. umbellata and S. kuznetzovii) are presented for the first time. The micromorphology of leaves and seed surfaces of the new species were investigated using SEM. A morphometric study using twenty characters from twelve specimens was carried out using principal coordinate analysis. The leaf architecture of S. erzincanica is very similar to that of the British local endemic S. pseudomeinichii, an autopolyploid apomictic species generated from several parents.