New late Tremadocian (Early Ordovician) conodont and graptolite records from the southern South American Gondwana margin (Eastern Cordillera, Argentina)

New late Tremadocian (Early Ordovician) conodont and graptolite faunas from the eastern and central belts of
the Eastern Cordillera (Jujuy Province, northwestern Argentina) are reported. The conodont fauna includes the
guide species Paltodus deltifer pristinus, Paltodus deltifer deltifer, and Acodus deltatus (sensu lato), in association
with other taxa, and the graptolites Aorograptus victoriae, Ancoragraptus cf. bulmani, and Adelograptus cf.
altus. Overlapping ranges of the recorded species allow for a partial correlation between the Acodus deltatus-
Paroistodus proteus and Aorograptus victoriae zones, and the Notopeltis orthometopa trilobite Zone. The conodont fauna includes a mixture of forms typical of the Baltoscandian and Laurentian provinces, respectively. The
Early Ordovician basin of northwestern Argentina may correspond to the Shallow-Sea Realm and Cold Domain
and probably records the development of a differentiated conodont province in the southern South American
margin of Gondwana.