Resumo

LIZCANO-GUTIERREZ, Sergio Antonio  e  RAMIREZ-PINILLA, Martha Patricia. Morphological characterization of the embryonary stages of the freshwater stingray Potamotrygon magdalenae (Elasmobranchii: Potamotrygonidae). Rev. acad. colomb. cienc. exact. fis. nat. [online]. 2022, vol.46, n.180, pp.697-713.  Epub 18-Set-2023. ISSN 0370-3908.  https://doi.org/10.18257/raccefyn.1650.

Potamotrygon magdalenae is a stingray belonging to the family Potamotrygonidae distributed in the Magdalena River basin. This species is considered of high priority for research according to the National Plan of Action for the Conservation and Management of Sharks, Rays, and Chimaeras of Colombia. The studies of embryonic development in chondrichthyans are limited due to the difficulty in obtaining the biological material and there are few developmental staging tables for ray species. Here we do a macroscopic morphological characterization of a series of developmental stages of P. magdalenae. Thirty individuals were studied, including embryos, fetuses, and neonates resulting from dissections and abortions of pregnant females caught by incidental fishing. It was possible to identify nine stages of development that were described, photographed, drawn, and measured. The embryonic development of this species broadly follows the patterns known for other chondrichthyans with minor differences in the rate of yolk sac absorption and the absence of protruding gill filaments from the spiracles, which may be related to its viviparity and intrauterine matrotrophy.

Palavras-chave : Pharyngula; Embryogenesis; Embryos; Neonates; Potamotrygon.

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