Late Ordovician conodont faunas from the Carnic Alps: new data from old collections

The pioneering study by Serpagli (1967), based on the two distinct Rifugio Nordio and Monte Zermula sections exposed in the western Carnic Alps, Italy, laid the foundation for subsequent research on the Ordovician conodont faunas of central-southern Europe. A rich and diverse assemblage was reported, still using the morphospecies concept, and numerous new taxa were described and illustrated exclusively through line drawings. The recent rediscovery of the original conodont residues in the University of Modena and Reggio Emilia (UNIMORE) paleontological collections enabled the description of additional conodont elements, a reassessment of broader taxonomic issues, and the first photographic documentation of the collection. The assemblage, composed of approximately 2000 elements, documents the Amorphognathus ordovicicus Biozone by the recovery of 17 species belonging to 15 genera. Since this likely represents a fauna complementary to that already defined by Serpagli (1967), any consideration of abundance is probably of limited value, and any additional taxonomic detail becomes correspondingly more significant. The rediscovered fauna confirms the dominance of Hamarodus brevirameus, Scabbardella altipes, and Amorphognathus spp., accompanied by less common taxa such as Dapsilodus mutatus, Eocarniodus gracilis, and Plectodina alpina. The new species Icriodella serpaglii is introduced. This assemblage, consistent with the Hamarodus brevirameus-Dapsilodus mutatus-Scabbardella altipes Biofacies, closely resembles coeval faunas documented elsewhere in the Carnic Alps and further confirms the distinctive exceptional nature of this geographic sector within the northern Gondwana margin.