The Maiandeua-Algodoal islands, located in the municipality of Maracanã, Pará, Brazil, have characteristic mangrove and restinga vegetation with several physiognomically distinct plant communities, with great potential for palynological studies. Because of its evident tourist potential, the area in question is strongly influenced by anthropic action. In this ecosystem, the Bignoniaceae family, considered to be eurypolar, is represented by the species Cydista aequinocüalis (L.) Miers, Distictella racemosa Urb., Distictella cuneifotia (DC.) Sandw. and Paragonia pyramidata (L. Rich.) Bur. The main objective of this work is to analyze the pollen grains of these species in order to compare the results obtained with those of species from other types of ecosystems. Adult floral buds were taken from the MG herbarium (Museu Paraense Emílio Goeldi, Belém). The Erdtman acetolysis method was used to prepare the slides. Pollen grain morphology was analyzed for size, shape, number of openings and exine stratification. The pollen grains were measured, described and photomicrographed in light and scanning electron microscopy. The size varies from medium to large, atremate (no apertures) except for those of Paragonia pyramidata, which are 3-columned. The ornamentation of the exine varies from punctate, reticulate to broadly reticulate. In order to separate the species by pollen morphology, a key was elaborated.
|
