A new species of the Gondwanan genus Cardiolaria Munier-Chalmas in the Sandbian of northwestern Argentina: Paleobiogeographic considerations

Abstract

A new species of afghanodesmatid, Cardiolaria benicioi, is recorded from Sandbian strata of northwestern Argentina. This species confirms the strong paleobiogeographic relationships between the western Argentina basin and other peri-Gondwanan areas. The Mid-Late Ordovician distribution of bivalves fit well into the Mediterranean Province defined upon brachiopod and trilobite faunas. Similitudes between Tremadocian and Floian bivalves from the western Gondwana and the peri-Gondwanan areas indicate that such 'Mediterranean' paleobiogeographic patterns can be traced back well into the Early Ordovician.