This study describes the development of anthers and pollen in heterostylic flowers of two species of Erythroxylum. The features of anthers and their developmental pattern, which is of the dicotyledonous type, do not vary according to morphs or species. The pollen grains of both morphs show differences in their morphology, development, and content stored as a reserve source. In both species, thrum (short-styled) flowers presented bicellular pollen grains, while pin (long-styled) ones yielded bi- and tricellular pollen grains. The presence of inviable pollen grains in the two flower morphs of both species and the malformation of one of the four microsporanges in the thrum flowers of E. campestre are noteworthy. We verified that features found both in the anther wall and in the pollen grains could be related to the reproductive success and adaptation of the species to the Brazilian savanna biome.

Key words: Tapetum, Distyly, Microsporogenesis, Microgametogenesis.