Integrative systematics of two Origanum (Lamiaceae) species endemic to Türkiye

İngilizce (OpenAlex)

The taxonomic literature frequently mentions a “close relationship” between the species Origanum saccatum and O. solymicum in many sources. However, Origanum species present problematic intrageneric systematics. Therefore, to clarify their systematic relationships, morphological data were analyzed statistically using PCA and results supported species-level separation of these taxa. The microscopic characteristics of the species were examined, and diagnostic characters were identified, such as non-glandular trichomes and sinuous epidermal walls. ITS-based phylogenetic relationships within the genus were investigated and analysis results strongly supported the clade consisting of O. saccatum, O. ayliniae, and O. sipyleum, indicating the presence of a phylogenetically consistent core group within the genus. Also, analysis results supported the recognition of O. solymicum as a distinct taxon. This study is the first to analyze the ITS region for O. solymicum. The species are related but taxonomically distinct. This study supports recognition of both taxa as distinct species and highlights the importance of an integrative approach for species delimitation.