Palynology and systematics of morinaceae

Pollen grains from all thirteen species of the three genera to be recognised in a forthcoming revision of the Morinaceae, Acanthocalyx, Cryptothladia and Morina, have been investigated by light and scanning electron microscopy. Fresh pollen of M. longifolia has also been studied by light, scanning electron and transmission electron microscopy. Three main pollen types are described and a key provided for their identification. Each pollen type occurs throughout a genus. Further division of two of these pollen types enables groups of species to be recognised. Functional aspects of the pollen are discussed, especially their unique pre-germinative processes. A cladistic analysis of pollen characters provides a hypothesis for their evalution and supports the classification proposed in the recent revision.