TAXOPITYS URUGUAYA NOV. SP. (CONIFEROPSIDA, TAXALES) DEL PÉRMICO DE URUGUAY

Abstract

A new species of Taxopitys, Taxopitys uruguaya from the Lower Permian (Sakmariano-Artinskiano) of the Melo Formation of Arroyo Seco (Department Rivera) Uruguay is described.lt is characterized by a heterogeneous parenchymatic/sclerenchymatic pith with secretory cells, cysts, and extends into the leaf gap. The primary xylem is mesarch with wedge-like projections; the secondary xylem tracheids have bordered pits on both tangential and radial wlls. The latter shows spiral thickenings. Growth rings are only faintly marked. Extemally the stern bears impressions of several pairs of rhomboidal leaf-traces. which show a spiral disposition. Comparisons were made with species of Taxopitys from South Africa, India. Brazil, and Russia, which showed that the new species is different, specially in regard to pith and xylem characters. Palynological data from the same sediments confirm the presence of undoubtly Coniferopsida in this flora.