Scanning electron microscopy (SEM) images of pollen grains A Desmopsis terriflora G.E.Schatz, T.Wendt, Ortiz-Rodr. & Martínez-Velarde, pollen grain without externally visible aperture(s) B exine sculpturing weakly rugulate to fossulate (-perforate) ornamentation C Desmopsis trunciflora (Schltdl. & Cham.) G.E.Schatz, pollen grain showing one (another one at the opposite side likely to be also present) aperture exine area D exine sculpturing weakly rugulate to fossulate (-perforate) ornamentation E Stenanona tuberculata G.E. Schatz & Maas, pollen grain without externally visible aperture(s) F exine sculpturing verrucate ornamentation.