Genetic structuring in the grooved carpet shell clam Ruditapes decussatus along the Moroccan coasts revealed by microsatellites

Abstract

The grooved carpet shell clam Ruditapes decussatus is an economically important bivalve species in Morocco. Assessment of genetic diversity and genetic structure is essential for sustainable exploitation and effective management of this bivalve. Ten microsatellite loci were examined at seven localities along the Moroccan coast to determine the genetic diversity and population structure of the natural population of R. decussatus. A total of 280 clams were analyzed. The highest value of heterozygosity and mean number of alleles were found in the Mediterranean population (He: 0.685 and Na: 7.77), this can be considered in breeding and restocking programs. Five out of seven populations of R. decussatus showed signals of recent bottlenecks. Additionally, significant genetic differentiation among populations was detected (Fst =0.03125, p-val =1.021e−26). Bayesian analysis, neighbor-joining, and DAPC revealed the existence of two main groups spread on both sides of the 25th parallel. The AMOVA highlighted a genetic heterogeneity with the Southern and North group. These findings provide valuable information for efficient management and restocking based on aquaculture production for the Ruditapes decussatus inhabiting the Moroccan coasts.