Pollen morphology of Fridericia Mart. (Bignoniaceae) from Brazilian forest fragments

Abstract

A pollen morphology study of 10 Brazilian native species of Fridericia (Bignoniaceae) from forest fragments was performed using light microscopy and scanning electron microscopy, in search of new characters that might increase knowledge of pollen morphology of the species, and also to help the taxonomic characterization of the genus. The pollen grains were acetolysed, measured, photographed, and described qualitatively. The quantitative data were analyzed by descriptive statistics and multivariate statistics. Non-acetolysed pollen grains were observed under scanning electron microscopy for further details of exine and pollen surface. The pollen grains are isopolar, medium to large, with circular to subcircular amb, oblate-spheroidal to subprolate, tricolporate, with long colpi, constricted or not, sometimes with margo, rounded or truncated at the polar ends, endoaperture lalongate, and microreticulate to reticulate exine, sexine thicker than nexine. The results indicate a stenopalynous genus, however, in some cases, it is possible to identify the studied species by the pollen morphology. Morphological considerations are also discussed.