Palinotaxonomia de espécies de Lepidaploa (Cass.) Cass. (Vernoniinae - Compositae) ocorrentes no Sudeste do Brasil

Abstract

The pollinic study of 23 species of Lepidaploa that occur in southeastern Brazil was done with the objetive of contributing to the pollinic characterization of these species and also evaluating its taxonomic position. The pollen grains were acetolysed, measured, described and ilustrated under light microscopy. For further details of pollen surface and aperture, non acetolysed pollen grains were analysed by scanning electron microscopy (SEM) and, subsequently, electron-micrographed. Characteristics of pollen grains like shape, size and constitution of exine and aperture were studied. The pollen of the species analysed in this study varies from medium or large in size, isopolar, suboblate, oblate spheroidal or prolate spheroidal, subtriangular ambit, small or large polar area, 3-colporate with echinolophate surface. A key to identify the studied species was made based on pollinic data. Pollen grains from Lepidaploa have four main brochus organization pattern of the echinolophate exine. Three of these patterns can be divided into subtypes according to the apertural lacune shape.