Microfitolitos de las Poaceae argentinas: I. Microfitolitos foliares de algunas especies del genero Stipa (Stipeae: arundinoideae), de la provincia de Entre Ríos

Abstract

The phytolith morphology belonging to the leaves of 8 species of Stipa (S. brachychaeta Godr., S. charruana Arechav., S. filiculmis Delile, S. hyalina Nees, S. neesiana Trin. et Rupr., S. papposa Nees, S. philippii Steud. and S. trichotoma Nees), present in the prairies of Entre Ríos Province, is described. A new terminology and descriptive methodology to define the phytolith assemblage of each species is used. Cluster analysis (UPGMA) and principal component analysis (PCA) were performed on the data of 49 morphological characters from the 8 phytolith assemblages (OTUs). The results define three groups, the first group inelude S. filiculmis and S. trichotoma assemblages, the second one with S. hyalina and S. neesiana assemblages and the third one with (S. brachychaeta + S. charruana) + (S. papposa + S. philippii) assemblages. The 8 phytolith assemblages show Arundinoideae affinity (sensu Twiss, 1992), and differ from the typical phytolith assemblages of other Poaceae subfamilies.