Formación Río Genoa (Pérmico Inferior, Cuenca Tepuel-Genoa, Chubut): nuevos datos sobre su contenido palinológico

GUTIERREZ, PEDRO. R.; BALARINO, MARÍA L.; ESCAPA, IGNACIO; CÚNEO, RUBÉN

Revista del Museo Argentino de Ciencias Naturales

Año: 2007 vol. 9 p. 125 - 152

1514-5158

Abstract: Río Genoa Formation (Lower Permian, Tepuel-Genoa basim, Chubut): New data about palynological content. A new palynological assemblage is documented from the Río Genoa Formation, Tepuel- Genoa Basin, Chubut, Argentina. The material was collected from the upper part of the Río Genoa Formation, at Ferraroti II locality. It comes from the same level of a megafloristic assemblage. The assemblage is poorly preserved, comprising mainly cingulizonate and laevigate spores, and bisaccate pollen grains. Sixty spore-pollen species were indentified, prevailing: Dictyophyllidites mortonii (de Jersey) Playford & Dettmann, Leiotriletes tiwarii Saxena, Punctatisporites microtumulosos Playford & Dettmann, P. sp. cf. P. dejerseyi Foster, Cristatisporites sp. cf. C. longispinosus Menéndez, Kraeuselisporites apiculatus Jansonius, K. punctatus Jansonius, K. sanluisensis Menéndez, Lundbladispora areolata Césari et al., Barakarites rotatus (Balme & Hennelly) Bharadwaj & Tiwari, Crucisaccites latisulcatus Lele & Maithy, Colpisaccites sp. cf. C. granulosus Archangelsky & Gamerro, Alisporites sp. cf. A. australis de Jersey, Scheuringipollenites maximus (Hart) Tiwari, S. circularis Césari et al., S. medius (Burjack) Dias-Fabrício, Corisaccites? sp. A, Hamiapollenites sp. A, Lueckisporites? spp., Lunatisporites? spp., Staurosaccites? sp. A and Pakhapites sp. A. The assemblage might be adscribed to the Pakhapites fusus-Vittatina subsaccata or Lueckisporites-Weylandites Biozones. The megaflora is adscribed to the Ginkgoites eximia Biozone, of Early Permian age (Sakmariano-Artinskiano?). This rich microflora represents a community dominated by Lycophyta and ferns, with gymnosperms and pteridosperms/glossopteridals.