ibclogo XVI International Botanical Congess

Abstract Number: 2556
Poster No. = 952


INNOVATIONS IN EOCENE VEGETATION OF SOUTHERN ARGENTINA


Zetter, R.*, Hofmann, C.-C.*, Draxler, I.#, Ferguson, D.K.*,Durango de Cabrera, J.§ & Del Vergel, M.§ * University of Vienna, Austria, # Geological Survey, Austria, § State University of Tucumán, Argentina


Sediments from N.E. Tierra del Fuego, Argentina contain a diverse palynoflora (90 taxa). The dinoflagellate cysts and pollen and spore assemblages constrain the age to Middle Eocene. The most abundant taxa are Nothofagus spp., Podocarpus spp. and ferns. Accessory genera prefering megathermal conditions (Cnemidaria, Bombax, Cupania etc.) are considered to be relics from the megathermal/humid early Eocene. Nothofagus, Podocarpus, Fuchsia and Gunnera favour more mesothermal conditions. Various Asteraceae, Malvaceae, Apiaceae, Valerianaceae and Rosaceae indicate that the transformation of the vegetation involved the participation of advanced families with light-demanding taxa. The different Rosaceae pollen are amongst the oldest on record.

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