Population genetic structure of neotropical mangrove species on the Colombian Pacific coast: Pelliciera rhizophorae (Pellicieraceae)

Pelliciera rhizophorae is a Neotropical mangrove species whose distribution is mostly restricted to the Pacific Coast, between the Gulf of Nicoya (Costa Rica) and the Esmeraldas River (Ecuador). In the Caribbean, patches of Pelliciera have been found in Nicaragua, Panama, and Colombia. The genetic variation and the population structure of P. rhizophorae were evaluated in six zones of the Colombian Pacific, using AFLP molecular markers. Of the 225 amplified fragments produced, 155 (69%) were polymorphic in 57 individuals of P. rhizophorae collected in the localities of Virudó, Charambirá, La Plata Island, Tumaco, Milagros, and Chontal. Genetic diversity within populations varied significantly, with the lowest levels of within-population variation ($H_{ep}$= 0.081 and 0.090, respectively) in La Plata Island and Tumaco; and the highest level of variation ($H_{ep}$= 0.187) in Chontal. In the Colombian Pacific, P. rhizophorae was significantly structured, with 26.5 percent of the variation found among populations, which was an evidence of substructure within populations. Genetic differentiation was not related to the geographic distance between zones. This suggests that the population dynamics of P. rhizophorae could be associated with historic processes influenced by ecological and environmental factors such as the movement of pollen by birds, the displacement of propagules by marine currents, and the spatial distribution of favorable habitats. /// Pelliciera rhizophorae es una especie de mangle neotropical cuya distribución está casi restringida a la Costa Pacífica, entre el Golfo de Nicoya (Costa Rica) y el río Esmeraldas (Ecuador). En el Caribe, se han encontrado parches de Pelliciera en Nicaragua, Panamá y Colombia. La variación genética y la estructura poblacional de Pelliciera rhizophorae en seis zonas del Pacífico colombiano fueron evaluadas utilizando marcadores moleculares AFLP, produciendo en total 225 fragmentos amplificados, de los cuales 155 (69%) fueron polimórficos en 57 individuos de Pelliciera rhizophorae colectados en las localidades de Virudó, Charambirá, Isla La Plata, Tumaco, Milagros, y Chontal. La diversidad genética dentro de poblaciones varió significativamente, mostrando en Isla La Plata y Tumaco los niveles de variación intrapoblacional más bajos ($H_{ep}$= 0.081 y 0.090 respectivamente) y en Chontal el nivel más alto de variación ($H_{ep}$= 0.187). En el Pacífico Colombiano, P. rhizophorae resultó significativamente estructurada con