Three new Lower Devonian dalmanitid trilobite taxa are recognized from the Talacasto Formation in Precordillera Basin, Argentina, which includes two monospecific genera (Ivanites leonorae n. gen., sp. and Aguaditaspis mediaspina sp.), one additional genus species left open nomenclature. These combine characters of subfamilies Dalmanitinae Vogdes, 1890 Synphoriinae Delo, 1935, challenging their ...