No abstract

Lychnophorinae comprises 19 genera and 117 species. Its representatives are found mostly in the rocky grasslands ("campos rupestres") of Minas Gerais, Bahia, and Goiás States, Brazil. This study presents a palynological investigation of 10 species belonging to the genus Piptolepis, endemic to the rocky grasslands of the Espinhaço Mountains, in Minas Gerais State. The plant material used in this investigation was obtained from specimens deposited in Brazilian herbaria. Pollen grains were processed by the acetolysis method, measured, described, and photomicrographed in light microscopy and scanning electron microscopy. Morphological observations revealed Piptolepis pollen to be large, prolate spheroidal in most species, 3-colporate, ectoapertures long, sexine subechinolophate or sublophate. Endoapertures vary from almost circular, lalongate or lalongate, with a median constriction observed only in three species. Three types of spines were identifi ed: prostrate and disorganized, elongated and narrow, and conical, erect, apex acute in the other species. This fi rst palynological study of Piptolepis species allowed the separation of representatives of the genus using pollen keys. The most signifi cant characters were pollen shape, ornamentation, endoaperture, and presence of median constriction in the endoaperture. The fi ndings presented here do not support the infrageneric classifi cation of Piptolepis, as pollen characters were not unique to any section.

ABSTRACT(Pollen morphology of the genus Eremanthus Less. (Vernonieae, Asteraceae)). In order to evaluate the signifi cance of the pollen morphology for generic and infrageneric taxonomy of the genus Eremanthus (Vernonieae, Asteraceae), and to provide additional data for its phylogenetic reconstruction, the pollen of 20 of the 23 species of the genus was examined using light and scanning electron microscopy. Acetolysed pollen grains were measured, described, and illustrated using light microscopy, while non-acetolysed pollen grains were analyzed using scanning electron microscopy. Pollen grains of these species are isopolar, oblate-spheroidal in most of the species, more rarely prolate spheroidal or suboblate, subtriangular amb, tricolporate and subechinolophate. Th e variation among quantitative characters does not correlate with the macromorphological subdivision of the genus or with the generic or specifi c limits.

Paralychnophora is an exclusively Brazilian genus that has few species and a confusing taxonomy. The current study aims to help us better understand this genus by analysing pollen grains from six Paralychnophora species. The pollen grains were acetolysed, analysed and photomicrographed under light microscopy. They were not acetolysed for the scanning electron microscopy analysis. Features such as shape, size, exine constitution and aperture were investigated. The species were separated in a pollen key, and their features were of great diagnostic value for the genus. The ornamentation pattern allowed separating P. patriciana from P. reflexoauriculata, and it grouped the other taxa. P. atkinsiae distinguished itself by the polar area index (PAI) size. P. bicolor, P. harley and P. glaziouana were easily separated from each other when other features such as size, shape, distance between the spines and aperture dimensions were analysed together.