Desarrollo embrionario en Urotrygon chilensis en las costas de Ecuador.

Abstract

Urotrygon chilensis, a ray belonging to the Urotrygonidae family that is distributed from the Gulf of Mexico to the coasts of Valparaíso in Chile, is a viviparous aplacental species, considered near threatened by the IUCN. In this study, the description and morphological and morphometric analysis were carried out through the growth phases of the embryos of U. chilensis, of which a total of 485 samples were obtained in the years 2013-2018 and 2024 through incidental fishing off the coast of Ecuador. 6 stages were described until the total reduction of the yolk, the results show that the LT-PT relationship is isometric which indicates that both variables have a proportional growth, the analysis between males and females show that there are no significant differences between the measurements given and in the years sampled there is no cycle of embryos in annual growth, since it was shown that in the different months there was no synchrony with the growth of the embryos.