Adenda y precisiones sobre la morfología polínica en Alvaradoa subovata (Simaroubaceae) y Roupala brasiliensis (Proteaceae)

Morphological observations on pollen grains of Alvaradoa subovata Cronquist (Simaroubaceae) and Roupala brasiliensis Klotzch (Proteaceae) obtained from TEM complement previous studies of Xifreda & Sanso (1998). With the aim of giving details of the morphology and accuracy to the descriptive terminology, exine stratification is described and new observations on pollen grains obtained from SEM are added.