Taurus, an Important Diversification Center for the Genus Aethionema (Brassicaceae): Four New Species from the Central Taurus Mountains in Türkiye

This paper explores the role of the Taurus Mountains in shaping species differentiation and biogeographical regions, including distinct ecological zones at various altitudes. The genus Aethionema is a monophyletic group in tribe Aethionemeae, subfamily Aethionemoideae (Brassicaceae), a sister group to the rest of the family. Aethionema has significant taxonomic complexity, particularly in Türkiye, where the genus has the highest species diversity. In this study, four new species (Aethionema kadriyeae, A. uysalii, A. beysehirense, and A. ermenekense) are described based on morphological, palynological and phylogenetic analyses. The diagnoses, detailed descriptions, distribution maps, and illustrations of the new species are provided. Pollen and seed morphology, including detailed measurements of size, ornamentation, and shape, is given. Phylogenetic analyses using DNA sequences from nuclear region (ITS) and chloroplast region (rpl32-trnLUAG) were conducted to determine the evolutionary relationships within the genus. Overall, this research provides new insights into the biodiversity and evolutionary history of Aethionema in Türkiye, highlighting the significance of the Taurus Mountains in supporting rich ecological diversity.