Seed micromorphology in Dactylorhiza Necker ex Nevski (Orchidaceae) and allied genera

Seeds of 21 taxa of the genera Dactylorhiza (incl. Coeloglossum), Gymnadenia (incl. Nigritella) and Pseudorchis were examined by light microscope and SEM. Qualitative and quantitative characters were analyzed. In Dactylorhiza, the seeds are fusiform, but some populations of D. viridis show clavate seeds. According to the ornamentation of the periclinal walls, 3 types of seeds are recognized in this genus.