Early Triassic conodonts and carbonate carbon isotope record of the Idrija-Žiri area, Slovenia

The first recovery of the conodont Hindeodus parvus from Žiri (Slovenia) a few years ago highlights this area for Early Triassic biostratigraphical study. Systematic sampling of five sections in the Idrija-Žiri area has yielded the new species Platyvillosus corniger sp. nov. and Neospathodus planus sp. nov. Based on these new species and other conodont elements collected here, nine discrete conodont Unitary Association (UA) zones are proposed for this area. In ascending order they are: Eurygnathodus costatus Zone (UA 1), Eurygnathodus hamadai Zone (UA 2), Foliella gardenae Zone (UA 3), Neospathodus robustus Zone (UA 4), Platyvillosus corniger Zone (UA 5), Platyvillosus regularis Zone (UA 6), Triassospathodus hungaricus Zone (UA 7), Triassospathodus symmetricus Zone (UA 8), and Neospathodus robustispinus Zone (UA 9). The conodont and δ13C data indicate that these conodonts span the Dienerian/Smithian (i.e. Induan/Olenekian) boundary interval to the Spathian, and they also indicate that Triassospathodus hungaricus Zone (UA 7) does not occur at the base of the Spathian. These conodont zones are valuable for stratigraphic correlation within Central and southern Europe, and they also promote a better correlation worldwide. Conodonts in the Idrija-Žiri area were adapted to a shallow-water environment in an epeiric ramp.