The Iberá Natural Reserve (Corrientes, Argentina) shows off a significant diversity of macrophytes, which, along with the chemical composition of its waters, profoundly influence the diversity of zooplankton communities. Testate amoebae play a crucial role in aquatic ecosystems. In Argentina, research on these organisms has been scarce thus far, requiring exhaustive studies on this group in the Iberá aquatic environments. For this study, sampling was conducted in June 2023 at Portal Carambola, where representative sites were selected, differentiating between vegetated and non-vegetated environments. Qualitative and quantitative samples were obtained, and in situ physico-chemical variables were measured. Testate amoebae were observed in vivo using an optical microscope, and specific literature was followed for taxonomic classification. Richness (S), β-diversity, and multiple β-diversity were analysed to compare the communities in the two environments and to determine the factors influencing them. Preliminary results demonstrated that testate amoebae communities in vegetated areas exhibited greater taxonomic richness (22 taxa) compared to communities in non-vegetated areas (8 taxa), with 6 taxa shared between the two. The β-diversity analysis, based on the Sörensen index (55%), suggests that the species composition of testate amoebae in both communities tends to differ between the two types of environments analyzed. The component most contributing to the observed differences is the βSNE (=30%). These results suggest that macrophytes provide resources and favorable environmental conditions that benefit a greater diversity of testate amoebae. Most of the exclusive taxa are found in vegetated areas, highlighting the specialization of some species in these resource-rich environments. The density and presence of macrophytes are key determinants for the diversity of testate amoebae communities. The reduction in macrophytes is associated with a decrease in taxonomic richness, underscoring their crucial role in these ecosystems.