Abstract
The bivalve molluscs Colpomya? sp. and Goniophorina (Cosmogoniophorina)? tenuicostata Harrington are recorded for the first time in the Arenigian Suri Formation (Famatina Range, western Argentina), and the new taxa Suria ovalis new genus and new species, and Redonia riojana new species 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 Formation was geographically related to these basins, and consequently, it could likewise be considered as a peri-Gondwanan area.