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1150664.Pdf (491.3Kb) PROGRAMA FONDECYT INFORME FINAL ETAPA 2017 COMISIÓN NACIONAL DE INVESTIGACION CIENTÍFICA Y TECNOLÓGICA VERSION OFICIAL Nº 2 FECHA: 15/03/2018 Nº PROYECTO : 1150664 DURACIÓN : 3 años AÑO ETAPA : 2017 TÍTULO PROYECTO : MIOCENE MARINE DIVERSITY ALONG THE COAST OF CENTRAL TO SOUTHERN CHILE ACROSS MULTIPLE TAXA DISCIPLINA PRINCIPAL : PALEONTOLOGIA GRUPO DE ESTUDIO : CS. DE LA TIERRA INVESTIGADOR(A) RESPONSABLE : SVEN NIKOLAUS NIELSEN DIRECCIÓN : CAMPUS ISLA TEJA S/N, EDIFICIO PUGÍN COMUNA : VALDIVIA CIUDAD : Valdivia REGIÓN : XIV REGION FONDO NACIONAL DE DESARROLLO CIENTIFICO Y TECNOLOGICO (FONDECYT) Moneda 1375, Santiago de Chile - casilla 297-V, Santiago 21 Telefono: 2435 4350 FAX 2365 4435 Email: [email protected] INFORME FINAL PROYECTO FONDECYT REGULAR MODIFICACIONES ACADÉMICAS El informe no presenta modificaciones académicas. PROJECT RESULTS: Describe the results of your research in reference to its original and/or modified Project objectives. The maximum extension of this section is 5 pages (Arial or Verdana font, size 10). Results The main objective of this project was to better know and understand early Miocene latitudinal gradients in Chile. For this, several fieldwork campaigns were conducted in the areas of Navidad, Arauco, Valdivia, Chiloé, Chonos islands, and Taitao peninsula to improve sampling intensity in the previously known regions and extend sampling towards the south. Several molluscan (and other) taxa new to science were discovered and geographic ranges of known species can be extended. The collections of Chilean fossils housed at the Paleontological Research Institution in Ithaca, USA, were visited and, as far as possible in only one week, revised and documented. A number of rare and undescribed taxa were identified and will be included in monographs on the respective molluscan groups. A few highlights for the areas: Navidad: Most new localities reproduced the typical well-known mollusk fauna. However, especially a lithologically unusual locality near Maitenlahue yielded undescribed taxa of mollusks (e.g. Trivia) and small decapod crabs. Previously not recorded brachiopods were collected from Punta Perro. Arauco: A 3-dimensionally preserved fish skull was found at Ranquil and described in the master thesis of J. Pérez as belonging to the genus Hypoplectrodes. This genus occurs today mostly off Australia and New Zealand and has one species off Chilean tropical oceanic islands (thesis J. Pérez attached). Our fossil represents the first fossil record for the genus and adds to the Miocene Chile- New Zealand connection previously reported for mollusks. Valdivia: Little information exists about fossil invertebrates of the Santo Domingo Formation. An undergraduate thesis in biology will review and extend the knowledge of this unit starting this semester. At least one new bivalve species (Panopea) is present in our collection. Chiloé: New collections extend the range of several taxa from Navidad down south. Also it is now possible to include the enigmatic locality Puñihuil in the Lacuy Formation, due to the findings of gastropods, a coral and a brachiopod known from Navidad or equivalent units. Two geology undergraduate theses on fauna and stratigraphy are starting this semester. Fieldwork included detailed stratigraphic logging of the ~100m vertical coastal bluff section at Cucao. Chonos islands: Unusual findings include decapod crabs and new echinoderms. A master thesis on the foraminifera, clarifying age and bathymetry, will be finished during 2018 (not listed because not inscribed during 2017). Taitao peninsula: Taxa found which are new to science include mollusks, decapod crabs, and echinoderms. We were able to limit the age of the poorly known islands in the center of Tres Montes gulf to the Miocene (submitted master thesis Robles attached). Additionally, we found previously unreported localities that are significantly younger in age, likely Pliocene-Pleistocene, which extend the fossil record of this age by 2°lat to the south. Problems The main obstacle for the execution of the project was that PI Nielsen had to step up as director of the newly created Institute of Earth Sciences at Universidad Austral de Chile (document attached). This was not foreseen and occurred simultaneous to the arrival of funds for the projects first year. As a consequence, the time dedicated to the project could not be met as promised and more than a quarter of the funds for the first year had to be returned to Fondecyt. While fieldwork was conducted and most samples are processed, classification of new taxa and writing of manuscripts are behind schedule. Start and development of the project were also hindered by the late arrival of funds, especially in the first year (July!), which effectively eliminated the envisaged work during winter holidays 2015. This resulted in postponing the trip to revise collections in the USA to the following year, disturbing the following plans. Both proposed international collaborators dropped out from the project as detailed below, so that the hypothesis on water temperatures could not be addressed and the part on foraminifera was severely crippled. Several students doing their theses within the frame of this project were hired before finishing. While this is certainly good for them, it delays progress of important parts of the project. Specific goals I) To establish and compare latitudinal diversity gradients of mayor taxonomic groups from the Chilean Miocene. There are few definite results yet for this goal. For foraminifera and ostracods, this is partly due to the unexpected early (forced) retirement of international collaborator Finger, which also resulted in him dropping out of this project. However, a master thesis on the latitudinal gradient of foraminifera (Chávez) will be finished during 2018. Chávez is now teaching paleontology at Universidad Central in Santiago, which clearly slowed down progress of her thesis. Work on decapod crustaceans is advanced for the Chonos islands including some other localities like Mocha island. Seven new species will be described from relatively few specimens (22), significantly increasing the overall diversity of Chilean Miocene decapods. Work on classification of fish otoliths along the gradient, not originally considered in the proposal, has begun in collaboration with German specialist Werner Schwarzhans. The number of new mollusk taxa discovered during this project seems to be higher for the northernmost area (i.e., Navidad), but geographic ranges can now be extended for taxa formerly limited to single areas (e.g. Mitridae formerly only reported from Chiloé were collected in areas both to the north and south). Results of analysis of spatiotemporal biodiversity pattern of chondrichthyan fishes were done by co-PI Rivadeneira and his (former) student Villafaña (attached publication Villafaña & Rivadeneira in press), leading to the conclusion that multiple environmental exogenous factors interacted with taxon traits during the Neogene, creating a mosaic of biogeographic dynamics. To understand changes in faunal and functional diversity (see also point IV below) for the Miocene, we first needed to get a better grip on more (geologically) recent changes. An analysis of changes in gastropods was published for the Pliocene-Quaternary by the two PIs of this project (attachment Rivadeneira & Nielsen 2017). II) To establish geographic patterns of different mayor and minor taxonomic groups from the Chilean Miocene (Naticidae, Muricidae, Protobranchia, Pectinidae). Work on the bivalve group Protobranchia (families Nuculidae and Nuculanidae) is conducted with master student L. Pérez and preliminary results were presented at several conferences (see there). After starting his thesis, Pérez was hired as curator of fossil invertebrates at Chiles National Museum of Natural History in Santiago, which clearly slowed down progress. Manuscripts on Naticidae, Lucinoidea, and Mitridae by PI Nielsen are advanced, while progress on Muricidae and Pectinidae is little. Understanding the driving factors for the evolution of latitudinal gradients is fundamental for our research and is treated in the attached publications by Rivadeneira et al. (2015) and Spano et al. (2016). with participation of co-PI Rivadeneira. Abstract Lucinoidea (Nielsen, Reich, Kiel): The Cenozoic species of Lucinidae, Ungulinidae and Thyasiridae from Chile are revised. Types and new material of the 13 species described by Philippi in 1887 are discussed and figured. Three new Neogene species are described: Lucinoma aaa sp. nov., Thyasira bbb sp. nov., and Thyasira ccc sp. nov. Abstract Naticidae (Nielsen): A total of twelve species of Naticidae are described from early Miocene deposits of coastal Chile. Four species are newly described and new combinations are proposed for six oothers. Several available names are synonymized. The naticid species represent all three currently recognized subfamilies and belong in seven genera. Aaa gen. nov. is erected for Natica striolata Sowerby, 1846. Newly described species are Bulbus bbb sp. nov., Euspira ccc sp. nov., and Falsilunatia ddd sp. nov. Abstract Mitridae (Nielsen): The two Miocene mitrid species described by Philippi in 1887 are revised. Mitra martini Philippi, 1887 is a junior homonym and is renamed and reclassified as Aaa bbb nom. nov. while Mitra chiloensis Philippi, 1887 is confirmed in Imbricaria Schumacher, 1817. Contrary to published statements, the original type material of both species is still available. The range of Aaa bbb nom. nov. is
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