Huemacaspis (Trilobita, Kerfornellinae) from the Late Ordovician of the Argentine Cordillera Oriental

摘要: Abstract The trilobite genus Huemacaspis PŘIBYL and VANĚK, 1980 is redescribed from well-preserved material the Santa Gertrudis Formation (early Caradoc), Argentine Cordillera Oriental. new species H. gallinatoensis described figured. widely distributed in southern part of Central Andean basin during early Caradoc it a key taxon for correlation different units Oriental Sierras Subandinas Argentina Bolivia. This one few records trilobites age found shallow shelf environments southwestern Gondwana. accommodated within Kerfornellinae, subfamily otherwise known Europe northern Africa. fauna suggests faunal exchange with latter regions indicating persistence broadly similar biogeographic pattern to that documented earlier Ordovician times.