Conservation Implications for the Iberian Narrow Endemic <i>Androsace cantabrica</i> (Primulaceae) Using Population Genomics With Target Capture Sequence Data

<i>Androsace cantabrica</i> (Losa & P. Monts.) Kress is a narrow endemic alpine plant restricted to a few high-elevation localities in the Cantabrian Mountains of northern Spain. Although currently accepted as a distinct species, its close morphological and phylogenetic affinity to related taxa such as <i>Androsace adfinis</i> and <i>Androsace halleri</i> has led to historical uncertainty about its taxonomic status and evolutionary origin. Here, we use the universal Angiosperms353 target capture kit to generate nuclear and plastid data from <i>A. cantabrica</i> and closely related species in section <i>Aretia</i>. We employ phylogenomic analyses to clarify species boundaries and population genomic analyses to inform conservation management, as well as flow cytometry and sequence-based analysis using allelic frequencies to estimate its ploidy level. Phylogenetic analyses based on nuclear loci support <i>A. cantabrica</i> as a monophyletic clade, distinct from both <i>A. adfinis</i> and the <i>A. halleri</i> and <i>Androsace laggeri</i> clades, although topological incongruence with plastid data suggests historical hybridization. Flow cytometry and allelic frequency-based analysis indicate that <i>A. cantabrica</i> is tetraploid, differentiating it from <i>A. halleri</i> and <i>A. laggeri</i>, which are diploid. Population structure analyses reveal a shallow genetic split between eastern and western groups (<i>F</i> _ST = 0.04485), with higher genetic diversity observed in the east. We estimated the species' distribution, population sizes, and threats, and classified it as Vulnerable under IUCN criteria B1ab(ii,iii) + 2ab(ii,iii). We recommend targeted in situ management, <i>ex situ</i> seed conservation, and the establishment of a micro-reserve. This study illustrates the utility of Angiosperms353 data for resolving both taxonomic questions and conservation strategies in polyploid, range-restricted species.