ABSTRACT
Genetic variability is one of the important criteria for species conservation decisions. This study aimed to analyze the genetic diversity and the population differentiation of two natural populations of Arapaima gigas, a species with a long history of being commercially exploited. We collected 87 samples of A. gigas from Grande Curuai Lake and Paru Lake, located in the Lower Amazon region of Amazônia, Brazil, and genotyped these samples using a multiplex panel of microsatellite markers. Our results showed that the populations of A. gigas analyzed had high levels of genetic variability, which were similar to those described in previous studies. These two populations had a significant population differentiation supported by the estimates of FST and RST (0.06), by Bayesian analysis (K = 2), and by population assignment tests, which revealed a moderate genetic distance.
Subject(s)
Fishes/genetics , Genetic Variation , Microsatellite Repeats , Animals , Bayes Theorem , Brazil , Evolution, Molecular , Fishes/classification , Genetics, PopulationABSTRACT
Lucifer faxoni (BORRADAILE, 1915) and L. typus (EDWARDS, 1837) are species first identified in the neritic and oceanic waters off the Amazon. Samplings were made aboard the vessel Antares at 22 stations in July and August, 2001 with a bongo net (500-µm mesh size). Hydrological data were taken simultaneously for comparative purposes. L. faxoni was present at thirteen of the fourteen neritic stations analysed, as well as at five of the eight oceanic stations. L. typus was present at three of the fourteen neritic stations and in one of the eight oceanic stations. The highest density of L. faxoni in the neritic province was 7,000 ind.m3 (St. 82) and 159 ind.m3 (St. 75) in the oceanic area. For L. typus, the highest density observed was 41 ind.m3 (St. 64) in the neritic province. In the oceanic province, the highest single density value was recorded at station 75 (5 ind.m3). Overall, L. faxoni typically presented the highest densities.(AU)
Lucifer faxoni (BORRADAILE, 1915) e L. typus (EDWARDS, 1837) são espécies identificadas pela primeira vez nas águas neríticas e oceânicas da Amazônia. As coletas foram realizadas a bordo do navio Antares em 22 estações em julho e agosto de 2001, com uma rede bongô (500 µm). Dados hidrológicos foram tomados simultaneamente para fins comparativos. L. faxoni esteve presente em 13 das 14 estações neríticas analisadas, bem como em 5 das 8 estações oceânicas. L. typus esteve presente em 3 das 14 estações neríticas e em 1 das 8 estações oceânicas. A maior densidade de L. faxoni na província nerítica foi de 7.000 ind.m3 (estação 82) e 159 ind.m3 (estação 75) na área oceânica. Para L. typus, a maior densidade observada foi de 41 ind.m3 (estação 64), na província nerítica. Na província oceânica, o maior valor de densidade foi registrado na estação 75 (5 ind.m3). No geral, L. faxoni tipicamente apresentou as maiores densidades.(AU)
Subject(s)
Animals , Biodiversity , Decapoda/classification , Brazil , Population Density , SeasonsABSTRACT
Lucifer faxoni (BORRADAILE, 1915) and L. typus (EDWARDS, 1837) are species first identified in the neritic and oceanic waters off the Amazon. Samplings were made aboard the vessel "Antares" at 22 stations in July and August, 2001 with a bongo net (500-µm mesh size). Hydrological data were taken simultaneously for comparative purposes. L. faxoni was present at thirteen of the fourteen neritic stations analysed, as well as at five of the eight oceanic stations. L. typus was present at three of the fourteen neritic stations and in one of the eight oceanic stations. The highest density of L. faxoni in the neritic province was 7,000 ind.m(-3) (St. 82) and 159 ind.m(-3) (St. 75) in the oceanic area. For L. typus, the highest density observed was 41 ind.m(-3) (St. 64) in the neritic province. In the oceanic province, the highest single density value was recorded at station 75 (5 ind.m(-3)). Overall, L. faxoni typically presented the highest densities.