Novel members of the order Picornavirales identified in freshwater from Guarapiranga reservoir in São Paulo

The global challenge of water resource availability is exacerbated by anthropogenic influences that promote the emergence of pollutants. Among these pollutants are microbiological agents, including viruses, which are ubiquitous in the biosphere and play a pivotal role in both ecological balance and the occurrence of diseases in animals and plants. Consequently, monitoring viruses in water sources becomes indispensable for the establishment of effective prevention, promotion, and control strategies. Within this context, the study focuses on the identification of novel viruses belonging to the Picornavirales order in freshwater from the Guarapiranga Reservoir in the state of São Paulo, Brazil. The samples were subjected to viral metagenomics. Our analysis led to the characterization of four distinct sequences (GinkV-05, AquaV_10, MarV_14, and MarV_64), which exhibited significant divergence compared to other members of the Picornavirales order. This remarkable diversity prompted the identification of a potential new genus within the Marnaviridae family, tentatively named Ginkgonavirus. Additionally, we characterized four sequences in a very distinct clade and propose the recognition of a novel family (named Aquaviridae) within the Picornavirales order. Our findings contribute valuable insights into the previously uncharted diversity of Picornavirales present in water sources, shedding light on an important facet of viral ecology and evolution in aquatic environments.