CARACTERIZACIÓN GENÉTICA DE Hoplias Malabaricus (CHARACIFORMES) EN EL RIO SAN JORGE, COLOMBIA

Overfishing in the San Jorge River region for catfish and Hoplias malabaricus, the next most important fish, has led to a decline in their populations. H. malabaricus does not present reproductive migration, staying in the swamps, increasing the fishing pressure on the species. The genetic characterization of the H. malabaricus populations makes it possible to establish the conservation status or its possibility of extinction. The genetic evaluation was carried out using microsatellites amplified with heterologous primers with 62 to 95% polymorphism, sufficiently informative for genetic-population analysis. The H. malabaricus populations presented high genetic variability (high heterozygosity), a sign of conservation in the studied localities. The H. malabaricus population presented a high structure and low gene flow, such that there are three subpopulations: Ayapel, San Marcos, and San Benito, the only locations where the species was found. Although the high heterozygosities show that the local populations are not in a process of inbreeding (increased risk of disappearance), the increase in pressure on this species can lead to its extinction. Therefore, studies of fishing biology and population dynamics should be carried out in the three localities to establish adequate management of the populations.