Karyological and taxonomical considerations on Epipactis cupaniana sp nov (Orchidaceae) from Sicily

A new species of Epipactis from the Madonie massif (Sicily), E. cupaniana C. Brullo, D'Emerico and Pulv. sp. nov., is described and illustrated. It is a nemoral species, occurring in Holm oak woods, and is characterized by a diploid chromosome complement of 2n = 2x = 38. In the metaphase I, the mother cells of the embryo sac contain 19 bivalents. With respect to morphology and karyotype structure, the new species shows a close relationships with E. helleborine and other allied species, such as E. meridionalis and E. schubertiorum, both occurring in southern Italy and Sicily. However, several morphological features, chromosome size, and differences in the heterochromatin distribution allow for a clear distinction between E. cupaniana and the above-mentioned species.