Abstract

VALLEJOS LEIZ, L; CRISAFULLI, A  and  HERBST, R. Siraty, una nueva localidad fosilífera con maderas y estípites de la Formación Tacuary (Pérmico superior), Paraguay. Rev. Mus. Argent. Cienc. Nat. [online]. 2018, vol.20, n.2, pp.283-296. ISSN 1853-0400.

Silicified fossil woods and arborescent stems from Siraty, a new fossiliferous locality of the Tacuary Formation (upper Permian), Paraguay, are described. The fern stipe Tuvichapteris solmsi Herbst (Marattiales), and the following taxa of Pinales Zalesskioxylon uniseriatum Pant & Singh, Agathoxylon ningahense (Maheshwari) Crisafulli & Herbst and Podocarpoxylon indicum (Bhardwaj) Bose & Maheshwari were identified. The assemblage adds to the paleoxylofloristic knowledge of this formation and allows paleobotanical, and paleoecological considerations. These woods grew in a mesophytic-mesoxerophytic forest similar to other coeval formations. Growth rings type “0” (Creber & Chaloner) suggest a paleoenviroment in which moisture and temperature requirements were optimal for growth, without marked seasonality. From the evolutionary point of view, low rays and mixed type pits were identified, with abietinoid trend. The Permian age is confirmed by the typical Neopaleozoic anatomical characters of the found taxa.

Keywords : Woods; Permian; Siraty; Tacuary Formation; Paraguay.