Gymnosperm pollen grains from the La Veteada Formation (Lopingian), Paganzo Basin, Argentina: biostratigraphic and palaeoecological implications

Abstract

ZAVATTIERI, A.M., GUTTIÉRREZ, P.R. & EZPELETA, M., January 2018. Gymnosperm pollen grains from the La Veteada Formation (Lopingian), Paganzo Basin, Argentina: biostratigraphic and palaeoecological implications. Alcheringa 42, 277–300. ISSN 0311-5518.

This work forms the concluding part of a series of systematic studies of typical Gondwanan Permian palynofloras from the type section of the La Veteada Formation in the Paganzo Basin, central-western Argentina. It deals with the description and/or illustration of the non-taeniate monosaccate, bisaccate and polysaccate gymnosperm pollen species that are richly represented in the La Veteada Formation and are attributed to 25 genera. These taxa are allied to, or derived from, a diverse range pteridosperms (corystosperms, peltasperms), conifers (including Voltziales) and cordaites; Ginkgoales, Cycadales and Gnetales also have some representation. The new species, Jugasporites vellicoites, is instituted and the new combination, Alisporites angustus (Ouyang & Norris) comb. nov. et emend., is proposed. New evidence to support a Lopingian age for the palynoflora, considered to be the youngest Permian palynoflora recorded hitherto in South America, is based on a summary of the published information about its composition, together with an assessment of previous records of the diversity of gymnosperm taxa analysed in this contribution. The co-occurrence of several species of taeniate pollen (described in a previously published part of our work) and the gymnosperm taxa documented here, which have not been reported before from South America, differentiates the palynoflora of the upper La Veteada Formation from all others so far described from this continent. The high ratio of pollen versus spores, plus the botanical and palaeoecological inferences of the gymnospermous component of the formation’s palynoflora, reflects a parent vegetation adapted to relatively dry conditions. Such a low-humidity environment is consistent with the sedimentological evidence, which suggests that, through the Lopingian, semi-arid to arid climates dominated the southern South American basins.

Ana María Zavattieri* ([email protected]) Unidad de Paleopalinología, Departamento de Paleontología IANIGLA, CCT-CONICET-Mendoza, Av. Adrián Ruiz Leal s/n, M5502IRA, Mendoza, Argentina; Pedro Raúl Gutiérrez ([email protected]) Museo Argentino de Ciencias Naturales ‘B. Rivadavia’—CONICET, Sección Paleopalinología, Área Paleontología, Av. Ángel Gallardo 470, C1405DJR Buenos Aires, Argentina; Miguel Ezpeleta ([email protected]) Centro de Investigaciones en Ciencias de la Tierra, Universidad Nacional de Córdoba—CONICET, Ciudad Universitaria, Av. Vélez Sarsfield 1611, X5016GCA Córdoba, Argentina.

Keywords:

• palynology
• Late Permian
• palaeoenvironments
• palaeoclimate
• Gondwana
• South America

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental material

The supplemental material for this paper is available online at https://doi.org/10.1080/03115518.2017.1410571

Acknowledgements

Special thanks are due to R. Astini who provided the palynological samples and the relevant geological and stratigraphic studies of the Famatina Range. Thanks to A. Moschetti (IANIGLA, CCT-CONICET-Mendoza) for palynological laboratory preparations of samples for light optical microscopy studies as well as to F. Tricárico who provided assistance for the SEM study. We also thank the reviewers Dr Clinton Foster, Geoscience Australia and Dr Natasha Barbolini, University of Amsterdam (The Netherlands) for their valuable help in providing critical and constructive comments of the manuscript, as well as Dr Sergio Archangelsky (Buenos Aires) who made a critical review of the original manuscript. We are also deeply grateful to Dr John McKellar, Senior Geoscientist of the Geological Survey of Queensland (Australia), for the English style and grammatical corrections, queries and critical suggestions and comments made that greatly improved the quality of the manuscript. We are also grateful to the Assistant Editor, Dr Stephen McLoughlin for his observations, comments, grammar corrections and constructive critiques.