Pollen morphology of species of Cissus (Vitaceae): an evaluation of ornamentation

Cissus (Vitaceae) occurs naturally in all states of Brazil and others countries of South America. This work was realized out the analysis of morphological characteristics of pollen of 30 Brazilian species. The pollen grains were processed with lactic acetolysis method to be measured, described and illustrated in light microscopy and non-acetolysed for analysis in scanning electron microscopy. Statistically the species were identified using principal component analysis (PCA) and hierarchical cluster analysis (HCA). As a result it was observed that pollen grains are medium in most species, 3-colporate. The ornamentation of the sexine varied and was an important character in the delimitation of species. We was concluded that the attributes of pollen distinguish most of the taxa of the genus, thus confirming the heterogeneity of pollen. It is hoped that his study contributes to a better understanding of the taxonomy of the genus and provides data for future phylogenetic analysis.