Format: ORAL

K. Romoleroux1, P. Muriel1, P. Sklenr2, C. Ulloa3, D.A. Espinel-Ortiz1, C. Romoleroux1, J. Calvo

1. Laboratorio de Botánica Sistemática. Pontificia Universidad Católica del Ecuador. Quito, Ecuador. 2. Department of Botany, Charles University in Prague. Praga, República Checa 3. Missouri Botanical Garden, Missouri, USA 4.Conservatoire & Jardin Bot Geneve, Ginebra, Suiza

The Ecuadorian pramos constitute a complex and heterogeneous biome, integrated by several ecosystems, whose plant composition vary according to climate, altitude, geology, biogeographic history, and disturbance degree. The uplift of the Andes and the Pleistocene glacial and interglacial events, in addition to anthropogenic activities, helped to consolidate the Andean plant communities. The present work is based on bibliographic data, field work, and the revision of herbaria collections, particularly QCA and MO. In our work, we have recorded 1897 vascular plant species, which is the highest number of species cited for this biome in Ecuador, (1682 Angiosperms, 210 Pteridophytes and five Gymnosperms), of which 1161 are native, 699 are endemic to Ecuador and 37 are introduced. We found that the 10 most diverse families in this biome were: Asteraceae, Orchidaceae, Poaceae, Melastomataceae, Campanulaceae, Cyperaceae, Rosaceae, Ericaceae, Polypodiaceae, and Lycopodiaceae; whereas the 10 richest genera were: Epidendrum, Elaphoglossum, Phlegmariurus, Calceolaria, Senecio, Gentianella, Valeriana, Miconia, Gynoxys, and Carex.  Ecuadorian páramos have a high percentage of endemism (40%), especially in the narrower and more fragmented altitudinal belt, these unique species contribute to the formation of complex communities that change from north to south and along altitudinal gradients. Although these páramos contain one of the highest numbers of native and endemic species in relation to their area, they are very vulnerable to environmental changes and other anthropogenic processes, that is why most of these species are now endangered. It is necessary to continue with the study of the páramos to have a complete and updated checklist of the flora species, which will serve as a basic tool for conservation and decision-making processes in this important Andean landscape.