Species delimitation among <i>Primula hirsuta</i> and related taxa (Primulaceae) confirms the existence of cryptic species in the Europeans Alps

Abstract Primula sect. Auricula is the largest plant clade endemic to Western European mountains and hence an important model to study speciation in mountain plants. Within this section, a clade of closely related and largely cryptic taxa, with P. hirsuta and P. pedemontana as its most prominent members, has remained taxonomically challenging. New taxa have indeed been described in the last decades, and both their taxonomic status and phylogenetic relationships remain to be thoroughly assessed. Here we use high‐throughput genomic data along with detailed morphological measurements to test for species delimitations in this species complex, illustrating how biodiversity can be shaped in a harsh environment. Our results confirm that P. apennina , P. cottia , P. grignensis and P. valcuvianensis all deserve species status. In addition, we highlight a new lineage and describe it as a seventh species in this clade: P. vallis‐gaudemarica sp. nov. This taxon is a narrow endemic, with a highly restricted distribution in a few adjacent valleys of the southwestern French Alps. Phylogenetic relationships between all species of this clade are clearly resolved and suggest that both adaptation to novel substrates and geographic divergence have led to recent speciation as well as ongoing divergence within species. We finally translate the outcomes of our detailed systematic study into a formal taxonomic revision of the clade.