ADDITIONAL MOLLUSCA (BIVALVIA AND ROSTROCONCHIA) FROM THE SURI FORMATION, EARLY ORDOVICIAN (ARENIG), WESTERN ARGENTINA

The bivalve molluscs Colpomya? sp. and Goniophorina (Cosmogoniophorina )? tenuicostata Harrington are recorded for the first time in the Aren igian Suri Formation (Famatina Range, western Argentina), and the new taxa Suria ovalis new genus and new species, and Redonia riojana new s pecies are proposed. Additionally, the rostroconchid Ribeiria spinosa Babin and Branisa is also described. Some taxa shared with the Acoite Formation (Cordillera Oriental, Northwestern Argentina) and the Sella Formation (Cordillera Oriental, Bolivia) suggest that the Suri Formati on was geographically related to these basins, and consequently, it co uld likewise be considered as a peri-Gondwanan area.