Salvia macrosiphon Boiss., a taxonomically complex species within the Lamiaceae family, is widely dis- tributed across various regions of Iran. This study investigates the floral morphological characteristics and anatomi- cal structures of the leaf midribs and petioles across 11 populations of this species. For morphological analysis, 10 flowering stems per population were examined, with 10 measurements taken for each floral trait. Anatomical studies involved the examination of five leaves and petioles per population. Data was analyzed using SPSS and PAST software. According to the ANOVA test, significant differences were detected among and within the examined characteristics. Furthermore, the PCA analysis explored that calyx length, calyx width, and calyx length width ratio were the more variable traits, which contained about 61 % of the total variations. A morphology-based UPGMA dendrogram di- vided the populations into two main branches. Anatomical studies revealed that all populations exhibited dorsi-ventral leaves, with notable variability in anatomical traits. PCA-biplot analysis identified distinct traits characterizing certain populations. The UPGMA clustering dendrogram based on anatomical data also revealed two distinct branches, with subgroups within each cluster. The clustering patterns based on morphological and anatomical characteristics were notconsistent, highlighting differences in the morphological and anatomical responses of these populations to environ- mental conditions. Additionally, the observed diversity may be attributed to the existence of intraspecific taxa. These findings underscore the need for a re-evaluation of the infraspecific taxonomy of S. macrosiphon to better understand its taxonomic complexity and ecological daptability
