Neogene woods from Cerro Pampa, Catamarca, Argentina

Por primera vez se da a conocer el registro de maderas angiospérmicas de Fabaceae de la localidadde Cerro Pampa (Catamarca). Estratigráficamente proceden de los sedimentos de la Formación Chiquimil quepertenece al Grupo Santa María, integrado por las formaciones San José, Las Arcas, Chiquimil, Andalhuala,Corral Quemado y Yasyamayo. La Formación Chiquimil está constituida por areniscas volcanoclásticas finas conlimolitas y arcilitas pardo amarillas, rojas y verde claro dispuestas en capas alternas. Uno de los leños presentacaracterísticas que permiten compararlo con las maderas de Paraalbizioxylon Martínez. Este taxón está presente en las localidades de Tiopunco (Tucumán), Río Agua Verde y Corral Quemado de la misma Formación(Catamarca) y en las sedimentitas neógenas de Termas de Río Hondo (Santiago del Estero). El otro fragmento esafín a Menendoxylon Lutz. La presencia de vasos solitarios no muy grandes (menos susceptibles a contraer embolia), múltiples cortos, agrupados y placas de perforación simples, son caracteres que contribuyen a la seguridadhídrica en climas cálidos y estacionalmente secos.For the first time, Angiosperm woods of Fabaceae from Cerro Pampa locality (Catamarca) are described. Stratigraphically, these woods come from the sediments of the Chiquimil Formation that belong to Santa María Group. The Chiquimil, San José, Las Arcas, Andalhuala, Corral Quemado and Yasyamayo formations integrate Santa María Group (Mio-Pliocene). The Chiquimil Formation is composed of small volcaniclastic sandstones yellowish-gray, green and brown limolites and mudstones in alternating layers. One of the fragments presents characters that match with Paraalbizioxylon Martínez. This genus has been cited for Tiopunco, Río Agua Verde and Corral Quemado localities from the same Formation. However, is presented in Neogene sediments of Termas de Río Hondo (Santiago del Estero). Another wood shows affinity with Menendoxylon Lutz. The presence of not very large solitary vessels (less susceptible to embolism), multiple short, grouped, and simple perforation plates are characters that contribute to water security in hot and seasonally dry climates.Fil: Baez, Johanna Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Crisafulli, Alexandra María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Moyano, Sebastián. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Herbst, Rafael. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentin

First fossil record in Tambería formation (Neogene) in Bolsón de Fiambalá, Catamarca province, Argentina: Palaeoenvironmental inferences through Leguminosae woods

The aim of this study is to report the first fossil wood record of Leguminosae in miocene sediments from Tambería Formation outcropping in the center-west of Catamarca province, Argentina. This Leguminosae specimen was found on levels of multi-colored sandstones that alternated with dark brown pelites and gray conglomerates. It is characterized by the presence of: semi-ring porous wood with vestured ornamented pits, helicoidal thickenings on the vessel walls, paratracheal parenchyma, homogeneous and multiseriate rays, all of which justify its assignment to Gleditsioxylon Müller-Stoll and Mädel. Six species are known and distributed in: Argentina, the United States, China and Japan in Miocene sediments coetaneous with sediments from Tambería Formation. The fossil wood specimen documented in this study is assigned to Gleditsioxylon fiambalense nov. sp. taking into account the combination of its anatomical features. Vulnerability and mesomorphy indices reveal its subtropical environmental condition which is not only typical of Gleditsia amorphoides, the current species, but also coincides with the palaeoenvironmental inferences derived from sedimentological research. This first paleontological record promises interesting analyses to understand the paleobiological and paleoecological aspects of the Tambería Formation and adds another new evidence to show the diversity of the neogene Leguminosae lignofloras of northern Argentina.Fil: Baez, Johanna Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Novelties in the xylotaphoflora from Chiquimil Formation (Miocene), Catamarca-Argentina

The purpose of this study is to present two new records of angiosperm woods from Cerro Pampa locality in Catamarca province, Argentina. Chiquimil Formation, a fossiliferous unit composed of volcaniclastic sandstones with intercalated mudstones from the late Miocene, outcrops in this locality. Fabaceae Menendoxylon vasallensis Lutz and Paraalbizioxylon caccavarie Martínez woods have been formerly recorded in this fossiliferous site. In this work, the oldest record of Malvaceae for Argentina is presented and described: Bastardioxylon antiqua nov. gen. et sp. whose most distinctive feature is the presence of rays with sheath cells in the secondary wood. Furthermore, Menendoxylon lutzi nov. sp. has preserved a parenchymatic pith with the presence of arthropod coprolites and fungal filaments. These associated organisms provide useful information on the paleoenvironment that prevailed in the area and indicate warm and seasonally humid conditions which are –in turn– sustained by the data derived from fossil biota and sedimentology. The two new angiosperm woods records from Cerro Pampa extend the composition and distribution of the paleoxyloflora components in Santa María Group.Fil: Baez, Johanna Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Crisafulli, Alexandra María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

First Miocene megafossil of arrowhead, alismataceous plant Sagittaria, from South America

The first pre-Quaternary representative of Alismataceae from South America is reported based on achenes of Sagittaria montevidensis from the Palo Pintado Formation (upper Miocene) in the south of Salta Province, Argentina. Achenes are laterally compressed, have a lateral beak and a single recurved seed inside them. The fruits were found both in the base (10 Ma) and the top of the formation (~5 Ma), suggesting similar environmental conditions during this time period. A cursory review of the Alismataceae family in the fossil record, with a special interest in those South American reports is given. During the Oligocene-Miocene Sagittaria may have arrived from tropical Africa to South America and thence to North America.Fil: Robledo, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina. Universidad Nacional del Nordeste; ArgentinaFil: Contreras, Silvina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina. Universidad Nacional del Nordeste; ArgentinaFil: Baez, Johanna Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Galli, Claudia Inés. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; Argentina. Universidad Nacional de Salta; Argentin