Dianthus × belkinii (Caryophyllaceae), a new hybrid taxon from Altai

Dianthus × belkinii is an intersectional hybrid newly described from the Republic of Altai (Talduair massif). This taxon was also noted in Mongolia (Bayan-Ulegei aimag). The article describes the morphological features of the new taxon and discusses its relationship with parental species. The described hybrid has intermediate morphological features between the parental species, most notable are the fringed corollas. The stems are sparsely branched, relatively tall and similar to those of D. superbus. The calyx lobes and bracts are transitional between D. superbus and D. versicolor. The limb of the corolla is cut for ⅓–¼ of its length into a few lobes. Cytometry data showed an identical ploidy level of the new taxon and its putative parent species. The average value of the relative DNA content is almost intermediate, however, somewhat closer to D. versicolor. The ITS sequences of D. × belkinii show characteristic double peaks, which may point to a hybridogeneous origin of the plants. Identical chloroplast DNA sequences with D. versicolor but differences to D. superbus suggests that D. versicolor may be the maternal parent of this hybrid. Based on these polymorphisms, it is possible to state that the ITS sequence and D. versicolor × superbus itself are of a hybrid nature, where D. versicolor and D. superbus are the parent forms.