A fossil spine, originally described as belonging to Perciformes from the Late Cretaceous Marília Formation, Bauru Basin, Southeastern Brazil, is here restudied based on paleohistology. In addition to the overall morphology of the spine, our histological results point to the presence of pseudolamellar bone with embedded star-shaped osteocytes. These results confirm the recent redescription of this specimen as a Siluriformes, and confirm the absence, so far, of Percomorpha in freshwater deposits from the Cretaceous of Brazil and South America.