A revision of the genus Armeria (Plumbaginaceae) in peninsular Italy and Sicily through an integrative taxonomic approach

The genus Armeria in peninsular Italy has been affected by taxonomic ambiguity for more than a century due to high mor-phological variability. We present a comprehensive revision of peninsular Italian and Sicilian Armeria species, using an integratedtaxonomic approach that combines molecular phylogeny, plant and seed morphometrics, and cytogenetics, taking advantage of spe-cies delimitation and data integration methods. Nuclear (ITS) and chloroplast (trnF-trnL, trnH-psbA, trnL-rpl32, trnQ-rps16)markers were sequenced to construct phylogenetic trees and conduct species delimitation using assemble species by automatic parti-tioning (ASAP), while seed and plant morphometric data were analysed using dimensionality reduction techniques and Gaussianmixture models (GMMs) for conducting Bayesian inference on species boundaries. The results support the hypothesis of 10 speciesendemic to the Italian peninsula. Armeria gracilis subsp. majellensis is no longer recognised as a distinct subspecies due to insuffi-cient differentiation from A. gracilis s.str., while the occurrence of A. canescens in Italy is definitively excluded. On the contrary, wepropose to raise A. gracilis var. pollinensis to species level, with its name lectotypified herein. A new identification key is provided.The findings confirm Italy as a second biodiversity hotspot for the genus, emphasizing the value of integrated data and methods toresolve taxonomically challenging groups, providing also a framework for future genus-wide revisions