Rincon, G. et al. 2020. Notes on the occurrence and gender-based morphological aspects of Potamotrygon motoro (Elasmobranchii: Potamotrygonidae) in the complex of the Viana lake system- Maranhão, Brazil. Revista Nordestina de Biologia. 27, 1 (fev. 2020). DOI:https://doi.org/10.22478/ufpb.2236-1480.2019v27n1.47179.