Helleborus odorus Waldst. & Kit. subsp. cyclophyllus (A. Braun) Maire & Petitm.
Helleborus odorus subsp. cyclophyllus is a Balkan endemic subspecies. It occurs in open forests, shrublands and meadows, mainly at the montane zone (700-1500 m), in the north and central part of the Balkan peninsula, from Mt Erymanthos in Peloponnisos to Albania, south Bulgaria and Serbia. The taxon is the unique representative of the genus Helleborus in Greece, as the presence of one more species, Helleborus orientalis, is not yet confirmed.
Flowering occurs in spring (March-April), before or during leaf emergence; leaves are deciduous. Flowers are large, with numerous stamens and 3-6 carpels. Perinath has 5 parts, coloured pale yellow-green, which persist even after fruiting. Inside the perianth, a series of honey-leaves attract pollinators.
Hellebores are poisonous plants that contain toxins, like helleborin. In ancient times, the plants were used for pharmaceutical purposes, while nowadays many varities and hybrids are used in horticulture.