Resumen

ZUCOL, Alejandro Fabián  y  BREA, Mariana. Phytolith systematics, guideline for a classificatory system. A study case in the Alvear formation (lower Pleistocene), Entre Ríos, Argentine. Ameghiniana [online]. 2005, vol.42, n.4, pp.685-704. ISSN 1851-8044.

The classification rules to establish a phytolith systematics are outlined, in such a way allowing a precise treatment and delimitation of their ranks according to the botanical nomenclatural code. The morphological terminology used is explained and these rules are applied to the predominant phytolith morphotypes of the Alvear Formation in their type area, Puerto General Alvear (Diamante department, Entre Ríos). Its sediments were deposited during an semiarid interval in typical Lower Pleistocene pampean conditions. Globulolithum gen. nov. ( G. Sphaeroechinulathum sp. nov., G. sphaeropsilathum sp. nov.), Aculeolithum gen. nov. ( A. rostrathum sp. nov., A. Acuminathum sp. nov., A. ancistrathum sp. nov., A. aciculathum sp. nov.), Flabelolithum gen. nov. ( F. euflabelathum sp. nov., F. complanathum sp. nov.) and Macroprismatolithum gen. nov. ( M. psilaristathum sp. nov., M. Denticulathum sp. nov., M. ondulathum sp. nov., M. excavathum sp. nov.) are described. This assemblage represents the first fossil record for this formation.

Palabras clave : Phytoliths; Classification rules; Alvear Formation; Lower Pleistocene; Entre Ríos; Argentine.