Seed micromorphology supports the splitting of Limnorchis from Platanthera (Orchidaceae)

Seeds of several species of the genera Platanthera and Habenaria have been studied by means of scanning electron microscopy. In the genus Platanthera, two morphological patterns were found. One of these appears in the so-called 'dilatata-hyperborea complex'. It is proposed that this pattern is a good diagnostic character to split off this group of species into the genus Limnorchis. In Habenaria, the morphological patterns vary between the species and differs completely from those found in Platanthera.