MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Pollen morphology of Asterales
Autor/es:
BARREDA, V. D.; LUIS PALAZZESI; TELLERÍA, M.C.; SONIA FONTANA
Lugar:
Salvador
Reunión:
Congreso; XIV International Palynological Congress ? X International Organisation of Palaeobotany Conference; 2016
Resumen:
The order Asterales comprises more than 10% of the Angiosperm species diversity. It includes 11 families(Alseuosmiaceae, Argophyllaceae, Asteraceae, Calyceraceae, Campanulaceae, Goodeniaceae, Menyanthaceae,Pentaphragmataceae, Phellinaceae, Roussaceae and Stylidiaceae), ca. 1723 genera and more than 26000 species. The largest family is Asteraceae with ca. 1600 genera and 23000 species. Most of these familiesinhabit in the Southern Hemisphere, only Asteraceae, Campanulaceae and some species of Menyanthaceaeare cosmopolitan. The current knowledge on pollen morphology is detailed in Asteraceae, Goodeniaceaeand Calyceraceae, but it is yet uneven and sparse in the remainder families. This unequal level of informationmake difficult to identify synapomorphies in cladistic contexts. In order to assess the pollen diversitywithin Asterales we examined pollen grains of 52 species belonging to 42 genera of Asterales (exceptingAsteraceae, Calyceraceae and Phellinaceae) under LM and SEM. Pollen grains within Asterales exhibit variedmorphology, they include monads or tetrads, single or compound aperture (tri-, tetra- or hexa-colpate, tri-,tetra- or hexa-porate or, tricolporate) and variable sculpture (scabrate, perforate-verrucate, microechinate,echinate, rugulate, striate or reticulate) and structure (tectate, semitectate, columellate or with compactaspect). Despite this degree variation most of the studied families are distinctive morphologically. A newpollen type in Rousseaceae was here identified. The large family Campanulaceae together the mediumsizedGoodeniaceae and the small family Rousseaceae, have the most diverse types of pollen. By contrary,the medium-sized family Stylidiaceae is fairly uniform in pollen morphology. This study shows the pollendiversity within Asterales and provides support for future taxonomic, phylogenetic and palaeontologicalstudies within the order.