Abstract

PEREZ LOINAZE, Valeria. Systematic palynological study of the Cortaderas Formation, (Mississippian) Río Blanco Basin, Argentina: Part Two. Ameghiniana [online]. 2008, vol.45, n.2, pp.421-441. ISSN 1851-8044.

Well preserved Mississippian palynological assemblages have been obtained from the Cortaderas Formation in the Río Blanco Basin, northwestern Argentina. In this second contribution, twenty- eight from a total of seventy-eight spore species are described. A new species of trilete spores is proposed: Densosporites scalabrinii sp. nov. Worldwide geographic and stratigraphic records of taxa are analysed. The Cortaderas Formation is dated as late Viséan in age based on the presence of species of potential stratigraphic relevance, such as Reticulatisporites magnidictyus Playford and Helby, Verrucosisporites quasigobbettii Playford and Helby and Rugospora australiensis (Playford and Helby) Jones and Truswell and the absence of pollen grains. The samples collected in the uppermost level of this unit, contain some of spores typical of the Upper Carboniferous of Argentina and Brazil, although pollen grains are still absent.

Keywords : Argentina; Cortaderas Formation; Mississippian; Palynology; Systematics.