Pinar, S.M.Fidan, M.Eroğlu, H.2025-05-102025-05-1020212602-456X10.31594/commagene.9541582-s2.0-85151137722https://doi.org/10.31594/commagene.954158https://hdl.handle.net/20.500.14720/5701In this study, the plant taxa that spread within the provincial borders of Siirt were determined by scanning the existing literature and as a results of the 2-year (2018-2019) field study. In the literature review, the existence of 786 taxa within the borders of Siirt province was determined. As a result of the field studies, 447 of these taxa were collected and recorded. In addition, with this study, it was determined that 89 new taxa are distributed in Siirt province. According to the results, it was determined that a total of 875 taxa are distributed within the provincial borders of Siirt and 71 of these 875 taxa are endemic (endemism rate 8.11%). Out of 95 taxa that are not endemic or endemic and are considered endangered are evaluated in categories as follows: 6 taxa "CR" Critical, 10 taxa are "EN" Endangered, 33 taxa are "VU" Vulnerable, 18 taxa are in "NT" Near Threatened, 23 taxa are in "LC" Least Concern, and 5 taxa are in "DD" Data Deficient. Of the detected taxa, 329 are Iran-Turan elements, 90 are Mediterranean elements, 35 are European-Siberian elements, and 4 are Euxine elements while 417 belong to a phytogeographical region or multi-regions. As a result of the study, the first five families with the most taxa are, respectively, Poaceae (115 taxa), Fabaceae (109 taxa), Asteraceae (95 taxa), Apiaceae (56 taxa), and Lamiaceae (53 taxa). © 2021, ABADER (Adıyaman Bilimsel Arastırmalar Dernegi). All rights reserved.trinfo:eu-repo/semantics/openAccessBiodiversityEndemicPlantTaxonArticle52N/AQ4991251110387