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This contribution reports two graptolite assemblages from the Puna Turbidite Complex, outcropping in Sierra de Lina and Cauchari locality, western Puna, Jujuy and Salta provinces, Argentina. In Sierra de Lina, the graptolite assemblage comprises Didymograptus sp., Glossograptus fimbriatus, Cryptograptus schaeferi, Archiclimacograptus sp., Pseudamplexograptus distichus, Pseudamplexograptus latus, ?Urbanekograptus retioloides and Hustedograptus sp. The graptolite fauna collected from Cauchari locality includes Didymograptus spp., Archiclimacograptus caelatus, Archiclimacograptus sp. cf. A. micidus, scarce and incomplete specimens doubtfully referred to the genera Archiclimacograptus and Acrograptus and scarce siculae of Cryptograptus sp. The associations allow us to identify the Pseudamplexograptus distichus Zone in Sierra de Lina and possibly the Pterograptus elegans Zone at Cauchari locality. Graptolite assemblages recorded in both zones allow assigning a middle‐late Darriwilian (Middle Ordovician) age for the bearer levels. [ABSTRACT FROM AUTHOR]

In this paper we compare the diversity of Floian (Lower Ordovician) conodonts from the Precordillera with that of the Cordillera Oriental, Argentina. The comparative analysis is restricted to the middle Floian Stage Slice (Fl2) from correlative intervals: Oepikodus evae Zone (Juanognathus variabilis Subzone) in the Precordillera and the Gothodus andinus Zone in the Cordillera Oriental. For the comparative analysis, absolute frequency tables of the conodont data from published articles and collections under study, were prepared. These include four sections of the Precordillera with 13 samples recovered from the middle section of the carbonate San Juan Formation, and six sections of the Cordillera Oriental with 28 samples from the middle-upper section of the shaly Acoite Formation. Diversity patterns and indices were generated from absolute frequencies using the software PAST 4.03. Remarkable differences in the species richness and diversity between coeval communities of referred basins are displayed. Comparisons with other basins elsewhere suggest that the paleolatitudinal gradient is not a major factor controlling changes in diversity, which may be due to a response to the complex interaction of biological and physico-chemical factors. • Conodont diversity in the Precordillera is higher than in Cordillera Oriental. • Conodont diversity is possibly controlled by physico-chemical and biological causes. • Paleolatitudinal gradient is not a major factor controlling changes in diversity. [ABSTRACT FROM AUTHOR]