Seed morphology of five Aeschynomene (Fabaceae) species from Pantanal

Seed shape, dimensions, surface texture, sculpture, hilum shape, and position were recorded for five Aeschynomene L. species (Fabaceae): A. denticulata, A. fluminensis, A. histrix, A. rudis, and A. sensitiva from Pantanal, Brazil, using a scanning electron microscope. The five species shared similar seed characteristics such as shape, color, surface, apex and base, face and side, hilar fissure, hilar sculpture and color, aril sculpture and color, micropylar pore position, and testa sculpture. Seed species differed in measurements (seed length and width, hilum length and width, and aril elevation). The hilum exhibited the position, shape, microsculpture, periclinal wall, and secondary sculpture of the testa, which are typical of some species. Two patterns were recognized based on the hilum shape, hilar area, and five hilum microsculpture surface patterns. Four patterns were recognized based on the testa periclinal wall, and three patterns were recognized based on the testa secondary sculpture. The results proved the potential taxonomic value of the recorded characteristics, as indicated by the richness of variation recorded in a limited sample of Aeschynomene species in the Pantanal wetland.