Temporal variation in the genetic diversity of a marine invertebrate with long larval phase, the muricid gastropod Concholepas concholepas

Larval dispersal affects population dynamics and thus the evolution of species; therefore, understanding how far planktonic larvae can move is key for the conservation and management of marine species. The degree to which genetic connectivity is temporally stable in marine environments is still largely unknown. Here we evaluated the temporal stability of the spatial genetic structure of the marine gastropod Concholepas concholepas, locally called the loco. This species has a wide geographic distribution along the southeastern Pacific, from Peru to southern Chile. The pelagic larval duration (PLD) of C. concholepas is three months. By comparing samples from eight spatially isolated sites in two different years (2006 and 2011), we analyzed the temporal and spatial variation of genetic diversity using 15 microsatellite loci. The results showed high levels of genetic diversity and high genetic differentiation between and within sample sites in both years. Our results suggest that there is temporal variation in gene flow direction probably drive it by oceanographic currents in the area and consequently larval dispersal at shorter distances might be expected. The Ne estimation suggests a complex demographic history and that inter-annual variability could affect the genetic structure in C. concholepas. This study highlights the importance of integrating temporal scales in the genetic studies of marine species.