Plant Biosystems, cilt.160, sa.3, 2026 (SCI-Expanded, Scopus)
Purpose: We present the first integrative taxonomic assessment of Petrosimonia in Türkiye by combining morphological and cytogenetic analyses, as well as a multilocus phylogenetic reconstruction. Methods: Specimens of Petrosimonia were surveyed across five regions and 27 provinces of Türkiye using literature, and herbarium specimens (stored at ANK, GAZI and HUB); diagnostic traits were reassessed and updated descriptions prepared. Seeds were collected for chromosome counts using root-tip pretreatment (8-hydroxyquinoline), Carnoy fixation, Feulgen staining, and microscopy imaging. DNA (silica-dried leaves) was sequenced for nrITS, atpB–rbcL, and psbB–psbH; datasets were aligned and analyzed with MP/ML/BI. Results: A greatly expanded Turkish records of Petrosimonia: 24 new localities for P. brachiata, 16 for endemic P. nigdeensis, 4 for P. glauca, and 2 new localities for P. squarrosa. Karyology showed that all taxa are diploid, with 2n = 16 in P. brachiata, P. glauca and P. squarrosa, and 2n = 14 in P. nigdeensis. Phylogenies (atpB–rbcL, psbB–psbH, ITS) recovered Petrosimonia as monophyletic and yielded congruent topologies, consistently placing P. brachiata as basal; the remaining relationships varied by marker but strongly supported major clades separating P. nigdeensis and grouping P. glauca with P. squarrosa in the nuclear ITS dataset. Additionally, P. squarrosa is lectotypified on a specimen held at both the Leningrad Herbarium (LE), with an isolectotype at LE the British Museum (BM). Conclusion: The integrative evidence generated in this study clarifies species boundaries, resolves phylogenetic relationships, stabilizes chromosomal data, and provides a substantially revised taxonomic and biogeographic framework for Petrosimonia in Türkiye, establishing a robust foundation for future evolutionary and conservation-oriented research.