Philorhizus marggii n. sp. is described from Greece (southern Peloponnese). Type locality: Taygetos Massif, Profitis Illias, N 36°58’/E 022°21’, 2000-2400 m asl. Members of this micropterous species are distinguished from the other Philorhizus species occurring on the Balkans by habitus, the special colouration pattern of the elytra and the special construction of the internal sac of the median lobe. Illustrations of the habitus, the median lobe and its internal sac and a description of the habitat of the new species are presented. A key to all Philorhizus species known from Greece is given. Biogeographic notes on the distribution of micropterous Philorhizus species in the western Palaearctic realm are given. Philorhizus paulo Wrase, 1995 is recorded from France for the first time (East Pyrenees).