FORAMINIFERA FROM THE AGRIO FORMATION (LOWER CRETACEOUS), NEUQUÉN BASIN, ARGENTINA. Forty-six species of benthic foraminifera recovered from the Pilmatué and Agua de la Mula Members of the the Agrio Formation are described and illustrated. The genus Eomarssonella and Epistomina hechti Bartenstein et al. are recorded for the first time in the Neuquén Basin, and Trocholina infragranulata North is found in the central area of the basin. The stratigraphic range of Epistomina australis Masiuk and Viña, Reinholdella hofkeri (Bartenstein and Brand), Trocholina infragranulata North, Marssonella sp. and Marssonella subtrochus Bartenstein is expanded to both marine members of the Agrio Formation. Differences recognized in the foraminiferal assemblages suggest marginal marine to marine inner-middle shelf environments. Nutrients, oxygen and salinity fluctuations are observed throughout the sedimentary sequence.