Taxonomic position and circumscription of Cardamine barbaraeoides (Brassicaceae), a systematically challenging taxon from the Balkan Peninsula

The Balkan Peninsula, and the territory of Greece in particular, is a significant biodiversity hotspot in the Mediterranean that is rich in endemic plants. The focal species of this study, Cardamine barbaraeoides, is a narrow Greek endemic that has been confused taxonomically since its original description. Based on a detailed multivariate morphometric study, we provide here a set of morphological characters that enables the reliable identification of this species. In addition, we present an identification key to C. barbaraeoides and related taxa. We have revised herbarium specimens and literature data on the occurrence of this species in Greece and ascertained that it occurs only in the Pindos mountains (the Southern Pindos and partly the Northern Pindos floristic regions). All reports of this species from the Greek floristic regions of North Central, Sterea Ellas and partly also Northern Pindos were based on misidentifications of specimens of C. acris.

Automated summary

The Balkan Peninsula, especially Greece, is a significant biodiversity hotspot in the Mediterranean region with many endemic plants. The study focused on Cardamine barbaraeoides, a Greek endemic species found only in the Pindos mountains, and provided reliable morphological characters for its identification. Reports of this species from other Greek floristic regions were based on misidentifications of specimens of C. acris.