Allium oreohellenicum Tzanoud., Tsakiri & Raus (Amaryllidaceae), endemic of the Greek mountains, is described and illustrated as a species new to science. Information regarding its cytology, geographical distribution and taxonomic relationships is also provided. Material belonging to A. oreohellenicum was formerly known/classified as A. achaium Boiss & Orph., a taxon described in 1882 based on a gathering by Orphanides from Mt Klokos (N Peloponnisos, Greece). A detailed study of the Orphanides gathering concerned revealed that it essentially belongs to A. frigidum Boiss. & Heldr., a taxon described 28 years earlier, and so the need for a new name.
