Anatomical Characterization of Achillea alimeana and Linum punctatum subsp. pycnophyllum from Southwestern Türkiye

Purpose: This study aimed to investigate the root, stem, leaf anatomy, and stomatal features of Achillea alimeana Semiz & Uysal and Linum punctatum Presl subsp. pycnophyllum (Boiss. & Heldr.) Gustavsson, two taxa with limited anatomical information from southwestern Türkiye. The study also aimed to evaluate the recorded anatomical characters as supplementary data for future taxonomic assessments.Method: Plant materials were collected from natural populations in Çameli district, Denizli Province, Türkiye. Root, stem, and leaf samples were fixed in 70% ethanol, dehydrated through a graded ethanol series, embedded in paraffin, and sectioned using a rotary microtome. Transverse sections were stained with the Safranin–Fast Green double-staining method and examined under a light microscope equipped with a digital camera system. Stomatal features were examined from superficial leaf sections. Quantitative anatomical measurements were based on 20 measurements for each evaluated character.Findings: A. alimeana was characterized by a circular root, octagonal stem, well-developed lamellar collenchyma at the stem corners, equifacial leaf structure, collateral vascular bundles, eglandular trichomes, and amphistomatic leaves with anomocytic and mesomorphic stomata. L. punctatum subsp. pycnophyllum showed a fragmented root periderm, circular stem, hypodermal layer, fibre cells, hollow pith region, equifacial mesophyll, collateral vascular bundles, and amphistomatic leaves with paracytic and mesomorphic stomata.Conclusion: The anatomical characters recorded in this study contribute to the structural characterization of both taxa. These findings provide additional anatomical data for A. alimeana and L. punctatum subsp. pycnophyllum and support the use of vegetative and stomatal anatomy as complementary evidence in taxonomic studies.