Micropaleontología de los calcáreos del Cámbrico Inferior de la Formación El Jagüleguito (Río Negro)

Abstract

The Cambrian Explosion (CE) was a three stage process of diversification that culminated with the appearance of a huge variety of marine animals during the Early Cambrian (541.0 - 521 mya). It is during the second stage of the CE that appeared various invertebrates groups which are currently called Small Shelly Fossils (SSFs) base on their preservation type and possible producers. This fauna has been described world wide, and for that reason they are useful as tools for paleobiogeographic correlation. Nonetheless, descriptions for South American material are made from thin sections, unlike the standard practice (microfossil imaging), with low diversity material (2 genera). In the present paper it’s presented the most diverse southamerican fauna (N=9) to date, obtained from three erratic clasts collected by González et al. 2011 in El Jagüelito Formation, Río Negro, Argentina, based on the hypothesis of a possible affinity with the clasts collected by Wrona 1989, 2003, 2004, 2009 in the antarctic península. The described fauna it’s not diverse enough nor well preserved enough to obtain conclusive results.