The oogonial aperture of Oedogonium decipiens var. decipiens (Oedogoniales, Chlorophyta) and its systematic significance

Pollen morphology of ten Brazilian species within the South American clade (ca. 20 species) of Symplocos section Barberina (Symplocaceae) was analyzed with scanning electron microscopy to assess their reported androdioecious breeding system. All species exhibited pollen dimorphism. Pollen from male individuals is well developed and 3-colporate, whereas that from morphologically hermaphroditic individuals is malformed, often completely fragmented, lacks cytoplasm, and has no germination pores. Our results suggest that the morphologically hermaphroditic species of S. section Barberina with malformed pollen are cryptically dioecious.