Pollen morphology of the Stemonaceae

A pollen-morphological survey of all four genera of the Stemonaceae at the light and electron microscope level is presented. Stemonaceae is a eurypalynous family. Stichoneuron pollen, up to now described as monosulcate, appears to be inaperturate. Pentastemona pollen is most deviating in Stemonaceae. Its sexine consists of elements that resemble Ubisch bodies very much. It shares several features with pollen of Peliosanthes (Convallariaceae) and Trillium (Trilliaceae). However, the closest relatives of Pentastemona could not be traced with the available pollen-morphological evidence.