Genetic variation of the spiny spider crab Maja brachydactyla in the northeastern Atlantic

Abstract

The spiny spider crab Maja brachydactyla is a decapod crustacean that inhabits the northeastern Atlantic, from the British Isles to Senegal, and is the target of intense fishing activity. In the absence of previous genetic studies, we describe the genetic variability and structure of this species along Atlantic European coasts, paying special attention to the northwestern Iberian Peninsula (Galicia), where this species may be overexploited. Analysis of 2 mitochondrial fragments and 9 microsatellites indicates that these populations maintain appreciable levels of genetic diversity, most of which are found within localities. This scenario could be explained by quite large effective population sizes and noticeable levels of gene flow. M. brachydactyla in the northeastern Atlantic do not show any signs of a genetic bottleneck, and effectively conform to a diverse metapopulation with limited structure. © Inter-Research 2008.