A 60-million-year Cenozoic history of western Amazonian ecosystems in Contamana, eastern Peru

PIERRE-OLIVIER ANTOINE; M. ALEJANDRA ABELLO; SYLVAIN ADNET; MYRIAM BOIVIN; ADRIANA CANDELA; LAURENT MARIVAUX; MAËVA J. ORLIAC; MARÍA ENCARNACIÓN PÉREZ; FRANÇOIS PUJOS; CÉLINE ROBINET

GONDWANA RESEARCH

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016

1342-937X

Weprovide a synopsis of ~60million years of life history in Neotropical lowlands, based on a comprehensive surveyof the Cenozoic deposits along the Quebrada Cachiyacu near Contamana in PeruvianAmazonia. The 34 fossilbearinglocalities identified have yielded a diversity of fossil remains, including vertebrates,mollusks, arthropods,plant fossils, and microorganisms, ranging from the early Paleocene to the lateMiocene??Pliocene (N20 successivelevels). This Cenozoic series includes the base of the Huchpayacu Formation (Fm.; early Paleocene; lacustrine/fluvial environments; charophyte-dominated assemblage), the Pozo Fm. (middle + ?late Eocene; marinethen freshwater environments; most diversified biomes), and complete sections for the Chambira Fm. (lateOligocene?late early Miocene; freshwater environments; vertebrate-dominated faunas), the Pebas Fm. (lateearly to early late Miocene; freshwater environments with an increasing marine influence; excellent fossil record),and Ipururo Fm. (late Miocene??Pliocene; fully fluvial environments; virtually no fossils preserved). Atleast 485 fossil species are recognized in the Contamana area (~250 ?plants?, ~212 animals, and 23 foraminifera).Based on taxonomic lists from each stratigraphic interval, high-level taxonomic diversity remained fairlyconstant throughout themiddle Eocene?Miocene interval (8-12 classes), ordinal diversity fluctuated to a greaterdegree, and family/species diversity generally declined, with a drastic drop in the early Miocene. ThePaleocene??Pliocene fossil assemblages from Contamana attest at least to four biogeographic histories inheritedfrom (i) Mesozoic Gondwanan times, (ii) the Panamerican realm prior to (iii) the time of South America?s