The Neotropical freshwater fish Ichthyoelephas longirostris (Characiformes: prochilodontidae) is a short-distance migratory species endemic to Colombia. This study developed for the first time a set of 24 polymorphic microsatellite loci by using next-generation sequencing to explore the population genetics of this commercially exploited species. Nineteen of these loci were used to assess the genetic diversity and structure of 193 I. longirostris in three Colombian rivers of the Magdalena basin. Results showed that a single genetic stock circulates in the Cauca River, whereas other single different genetic stock is present in the rivers Samaná Norte and San Bartolomé-Magdalena. Additionally, I. longirostris was genetically different among and across rivers. This first insight about the population genetic structure of I. longirostris is crucial for monitoring the genetic diversity, the management and conservation of its populations, and complement the genetic studies in Prochilodontidae.

Prochilodus magdalenaeis a freshwater fish endemic to the Colombian Magdalena-Cauca and Caribbean hydrographic basins. The genetic structure patterns of populations of different members ofProchilodusand the historic restocking of its depleted natural populations suggest thatP. magdalenaeexhibits genetic stocks that coexist and co-migrate throughout the rivers Magdalena, Cauca, Cesar, Sinú and Atrato. To test this hypothesis and explore the levels of genetic diversity and population demography of 725 samples ofP.magdalenaefrom the studied rivers, we developed a set of 11 species-specific microsatellite loci using next-generation sequencing, bioinformatics, and experimental tests of the levels of diversity of the microsatellite loci. The results evidenced thatP. magdalenaeexhibits high genetic diversity, significant inbreeding coefficient ranging from 0.162 to 0.202, and signs of erosion of the genetic pool. Additionally, the population genetic structure constitutes a mixture of genetic stocks heterogeneously distributed along the studied rivers, and moreover, a highly divergent genetic stock was detected in Chucurí, Puerto Berrío and Palagua that may result from restocking practices. This study provides molecular tools and a wide framework regarding the genetic diversity and structure ofP. magdalenae, which is crucial to complement its baseline information, diagnosis and monitoring of populations, and to support the implementation of adequate regulation, management, and conservation policies.

Species of the family Lutjanidae constitute an important fishery resource in tropical marine areas worldwide and are intensely exploited because of their excellent commercial value and quality. In Colombia, the lane snapper Lutjanus synagris is considered vulnerable to overfishing due to its biological characteristics, habitat deterioration, and historical decrease in catch rates in regions where it used to comprise the highest percentage of the landings. In order to generate more biological information needed to make effective fishery management decisions and policies, the genetic structure of L. synagris was analyzed in three areas of the Colombian Caribbean (Santa Marta, Rosario Islands, and Capurganá) using microsatellite-type molecular markers. Fourteen primers reported for two phylogenetically close species (Rhomboplites aurorubens and Lutjanus campechanus) were analyzed, eight of which were polymorphic and informative for the species under study. All loci were found to depart from Hardy-Weinberg equilibrium due to marked heterozygote deficiency in all the populations studied. Both the analysis of molecular variance (total population ΦST = 0.006, P = 0.022) and spatial analysis of molecular variance showed a slight statistically significant population structure (best FCT = 0.003, ΦST = 0.007, P = 0.0001) that separated the Capurganá population from those of the other areas with no evidence of isolation by distance (Mantel test Rxy = 0.023, P = 0.057). The results suggest that the life history of the species and the regional oceanographic conditions play an important role in determining the genetic structure and the existence of two different genetic stocks that should be managed according to their population structure.

Curimata mivartii is a detritivorous species Neotropical, which is of great importance to local fisheries and riverine ecosystems. In this work, the mitochondrial genome of C. mivartii was completely sequenced using a combination of 454 FLX(+) platform and Sanger/capillary sequencing. The mitogenome is 16,705 bp in length, encodes 13 proteins, 22 tRNAs, 2 ribosomal RNAs and exhibit perfect synteny with others Characiformes.