First Dapingian linguliform microbrachiopods from the Argentine Precordillera (Cuyania terrane): Taxonomy and faunal relationships

Abstract

bstract New records of linguliform brachiopods from the Middle Ordovician of Argentina, coming from the base of the Gualcamayo Formation, are described and illustrated. The sampled levels correspond to the first 3 m at the Potrerillos Creek section, Argentine Precordillera of San Juan, assigned to the lower part of the Baltoniodus navis Zone (middle Dapingian). The fauna consists of the lingulids Palaeoglossa? sp., Elliptoglossa vulgaris Hansen and Holmer and Paterula sp., together with the acrotretids Conotreta andina Lavie´, Serra and Feltes, Scaphelasma zharykensis Popov, Torynelasma? sp., Numericoma simplex?, and Eoconulus sp. This relatively diverse association is the first of Dapingian age in the Cuyania terrane with a mixed fauna, which shows affinities with the regions of Baltica, Bohemia, Avalonia, South China, and Laurentia