Morphological aspects of the digestive system in freshwater stingray (Potamotrygon amandae—Loboda and Carvalho, 2013): myliobatiformes; potamotrygoninae - Aquino, Júlia Bastos de; Melo, Luana Felix de; Rodrigues, Rosângela Felipe; Melo, Alan Peres Ferraz de; Pinto, Luciano de Morais; Rici, Rose Eli Grassi (Zoomorphology, 2023)