Morphological and distributional characteristics of natural Sideritis L. taxa in Isparta province (Türkiye)

This study was conducted between 2020 and 2023 through fieldwork carried out across the Isparta province in southwestern Türkiye, aiming to determine the distribution, morphological characteristics, and habitat preferences of species belonging to the genus Sideritis. As a result of the research, a total of 14 taxa were identified in the region (S. condensata Boiss. & Heldr., S. congesta P.H. Davis & Hub.-Mor., S. cilicica Boiss. & Balansa, S. dichotoma Huter, S. erythrantha Boiss. & Heldr. subsp. erythrantha, S. hispida P.H. Davis, S. libanotica Labill. subsp. libanotica,, S. libanotica Labill. subsp. linearis (Benth.) Bornm., S. leptoclada O. Schwarz & P.H. Davis, Sideritis perfoliata L., S. pisidica Boiss. & Heldr., S. phrygia Bornm. S. syriaca L. subsp. nusairiensis (Post) Hub.-Mor. and S. stricta Boiss. & Heldr.). Twelve of these taxa, excluding S. libanotica subsp. libanotica and S. perfoliata, are endemic to Türkiye. Morphological characters of each taxon, such as leaf and flower structure, were measured in 50 individuals. The tallest plant was recorded as S. perfoliata (81.1 cm), while the shortest was S. condensata (24.7 cm). The habitats in which these taxa were observed typically included stony and rocky slopes, forest gaps, maquis clearings, and roadsides. These sites were found on slopes ranging from 5% to 45% and at elevations between 331 m and 2565 m. These results indicate that Sideritis species exhibit broad ecological tolerance and can adapt to a wide range of altitudinal zones.