MEGAFLORA DEL PENNSYLVANIANO DE LA SIERRA DE LOS LLANOS, LA RIOJA, ARGENTINA

COTUREL, ELIANA P.; GUTIÉRREZ, PEDRO RAÚL; BARREDA, VIVIANA D.

REVISTA BRASILEIRA DE PALEONTOLOGIA

SOC BRASILEIRA PALEONTOLOGIA

Lugar: Porto Alegre; Año: 2009 vol. 12 p. 17 - 26

1519-7530

FOSSIL FLORA FROM THE PENNSYLVANIAN OF SIERRA DE LOS LLANOS, LA RIOJA, ARGENTINA. Fossil plant assemblages from the Pennsylvanian of Sierra de Los Llanos range, La Rioja Province, are described in this contribution. They come from the La Huerta and Santa Bárbara sections, cropping out in the northeastern flank of the Sierra de Los Llanos range. La Huerta section, referred to the Solca Formation, yielded a diverse macrofossil assemblage composed by conifers (Paranocladus? fallax Florin), dispersed seeds (Samaropsis nunezii García emend. A. Archangelsky, Eucerospermun nitens Feruglio emend. A. Archangelsky), cordaitals [Cordaites sp. cf. C. hislopi (Bunbury) Seward], lycophytes (cf. Bumbudendron vermiforme Gutiérrez et al.) and pteridosperms (Eusphenopteris sp.). This assemblage is provisionally referred to the Megafloristic Interval Biozone, latest Carboniferous in age. Santa Bárbara section, assigned to the lower Loma Larga Formation, yielded remains of the lycophyte cf. B. versiforme. This assemblage is referred to the NBG Biozone (Nothorhacopteris argentinica-Botrychiopsis weissiana-Gynkgophyllum diazii) that characterizes the Pennsylvanian of western Argentina.