Malvaceous wood from the Late Pleistocene El Palmar Formation of northeastern Argentina

We describe a new species of Bastardiopsis, Bastardiopsis palaeodensiflora sp. nov., which is the first fossil Malvaceae wood reported in Argentina. It was collected from the Arroyo Yuquerí of El Palmar Formation, a late Quaternary fluvial unit, located in the middle Uruguay River Basin, NE Argentin...

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Detalles Bibliográficos
Autores: Ramos, Rita Soledad, Brea, Mariana, Krohling, Daniela Mariel Ines
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/65068
Acceso en línea:http://hdl.handle.net/11336/65068
Access Level:acceso abierto
Palabra clave:Bastardiopsis
El Palmar Formation, Argentina
Late Pleistocene
Malvaceae
Uruguay Basin
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descripción
Sumario:We describe a new species of Bastardiopsis, Bastardiopsis palaeodensiflora sp. nov., which is the first fossil Malvaceae wood reported in Argentina. It was collected from the Arroyo Yuquerí of El Palmar Formation, a late Quaternary fluvial unit, located in the middle Uruguay River Basin, NE Argentina. The diagnostic features of this fossil wood are growth ring boundaries demarcated by marginal parenchyma; diffuse porous wood; vessels solitary and in radial multiples of 2–3 elements; alternate and minute-to-small sized intervessel pits; tyloses abundant; vessel-ray parenchyma pits similar in size and shape to intervessel pits; vasicentric, and diffuse axial parenchyma; rays of two distinct sizes, mostly 4–5 cells wide; prismatic crystals in upright and/or square marginal cells, sheath cells, non-septate fibres, rays and vessel elements irregularly storied. These features suggest an assignation to Bastardiopsis (K. Schumann) Hassler, a genus with five extant species, extending from the north of South America to northern Argentina, mainly distributed in tropical to temperate areas. The eco-anatomical features, the Nearest Living Relatives (NLRs), the Vulnerability Index, the Mesomorphy ratios and the Taxon Independent Approach (TIA) indicate that this fossil grew under temperate-warm and humid conditions. This is consistent with other proxies (geological, sedimentological and microfossil data) suggesting a similar environment for this region during some periods of the Late Pleistocene.