ABSTRACT
The comparative phylogeography of marine species with contrasting dispersal potential across the southern Caribbean Sea was evaluated by the presence of two putative barriers: the Magdalena River plume (MRP) and the combination of the absence of a rocky bottom and the almost permanent upwelling in the La Guajira Peninsula (ARB + PUG). Three species with varying biological and ecological characteristics (i.e., dispersal potentials) that inhabit shallow rocky bottoms were selected: Cittarium pica (PLD < 6 days), Acanthemblemaria rivasi (PLD < 22 days), and Nerita tessellata (PLD > 60 days). We generated a set of SNPs for the three species using the ddRad-seq technique. Samples of each species were collected in five locations from Capurganá to La Guajira. For the first time, evidence of a phylogeographic break caused by the MRP is provided, mainly for A. rivasi (AMOVA: ΦCT = 0.420). The ARB + PUG barrier causes another break for A. rivasi (ΦCT = 0.406) and C. pica (ΦCT = 0.224). Three populations (K = 3) were identified for A. rivasi and C. pica, while N. tessellata presented one population (K = 1). The Mantel correlogram indicated that A. rivasi and C. pica fit the hierarchical population model, and only the A. rivasi and C. pica comparisons showed phylogeographic congruence. Our results demonstrate how the biological traits of these three species and the biogeographic barriers have influenced their phylogeographic structure.
ABSTRACT
Abstract The crevalle jack Caranx hippos, has a wide distribution in the Western Atlantic, becoming one of the most economically important species in the artisanal fishing industry in Colombia. However, little is known about its biology. The present study aimed to evaluate the variation and genetic structure of C. Hippos in the Colombian Caribbean by analyzing the mitochondrial DNA region control and cytochrome oxidase subunit (COI). We sequenced the DNA of 153 muscle samples collected from specimens obtained from six fishing ports. The results showed 21 haplotypes for COI and 116 haplotypes for the control region, divided into two lineages that do not exhibit a pattern of geographical distribution. For mitochondrial control region, the estimated haplotype diversity (Hd) presented relatively high values (Hd= 0.99 and = 0.1), while for COI results were Hd = 0.68 and = 0.01; the relationship between haplotype and nucleotide diversity and the neutrality test revealed that C. Hippos experienced bottlenecking and a subsequent rapid population expansion. Estimates of genetic structure were low and insignificant, indicating no differentiation between samples collected from geographical isolation. This suggests that for the Colombian Caribbean there is a panmictic population of C. hippos. However, variations were found at population levels, especially in La Guajira, Turbo and San Antero, which, when compared to those included for Brazil and México, demonstrated that unique haplotypes in La Guajira are more aligned to the Brazilian populations, by means of the influence of the Caribbean Current, whilst those from Turbo and San Antero are more frequent in haplotypes originating from Mexico. Future studies should focus the understanding of these processes. Rev. Biol. Trop. 66(1): 122-135. Epub 2018 March 01.
Resumen El jurelCaranx hipposes considerado una de las principales especies objeto de la pesquería artesanal en aguas colombianas; sin embargo, es poco lo que se conoce respecto a su estructura poblacional. El presente estudio propuso evaluar la variación y estructura genética en el Caribe colombiano a partir del análisis de la región control y la subunidad citocromo oxidasa I (COI) del ADN mitocondrial. Secuenciamos el ADN de 153 muestras de músculo recolectadas de ejemplares desembarcados en seis puertos pesqueros. Los resultados mostraron 21 haplotipos para COI y 116 haplotipos para la región control, distribuidos en dos linajes que no presentan un patrón de distribución geográfica. Para la región control la diversidad genética fue alta (Hd=0.99 y π = 0.1), mientras que para COI los resultados fueron Hd=0.68 y π =0.01, esto mostró que probablemente C. hipos pasó por un evento que provocó la disminución drástica de la población y posteriormente tuvo un crecimiento rápido. Las estimaciones del grado de estructuración genética fueron bajas y poco significativas indicando la ausencia de diferenciación entre las muestras recolectadas a partir de un aislamiento geográfico, esto sugiere que la población de C. hipos es panmictica; sin embargo, se hallaron variaciones a nivel intrapoblacional especialmente en La Guajira, Turbo y San Antero, los cuales al ser comparados con los haplotipos incluidos de Brasil y México se encontró que el único haplotipo hallado en La Guajira está alineado con el de Brasil, facilitado probablemente por la corriente del Caribe, mientras que los de Turbo y San Antero con los de México.
