PALEOBOTANICAL RECORD FROM THE DESCANSO-YAURI BASIN, PERU: INSIGHTS INTO THE NEOGENE ELEVATION HISTORY OF THE CENTRAL ANDEAN PLATEAU
Ten permineralized wood specimens were found in the late Miocene localities, together with one palm leaf morphotype, and abundant Podocarpaceae pollen. Wood anatomical characters suggest a tropical lowland canopy tree assemblage. Three wood specimens belong to the legume family (Fabaceae). Tree-height estimations for one of legume specimens suggest more than 35 m.
Abundant leaf material in the Pliocene localities was studied including Equisetum, Polystichum, Berberis, Polylepis, Ribes and tentatively Baccharis, The palynological record was mostly dominated by grasses and herbs.
The paleobotanical record suggests that by the late Miocene the Descanso-Yauri basin was dominated by a low to mid elevation tropical forest, and the basin elevation could not be higher than 2500 m. In contrast the paleobotanical record of the early Pliocene (~5 Ma) suggest highland conditions with a vegetation similar to today’s ecosystem. Our results supports the hypothesis of a rapid regional surface uplift of the northern Central Andean Plateau between ca. 10 and 6 Ma.