Figure 3 from: Robinson H, Skvarla J (2014) Pantoporate pollen in the Asteraceae (Vernonieae). PhytoKeys 38: 1-13. https://doi.org/10.3897/phytokeys.38.7495

Figure 3 - Scanning electron micrographs of Oocephala stenocephala (A–B from Christensen & Chisumpa 1508) and Polydora angustifolia (C from Christensen & Patel 1457). A intact grain with four visible pores B intact grain with one visible pore C grain partially stripped of muri showing three pores in pantoporate positions