This document summarizes a study on the genetic diversity of solea atlanto-mediterranean populations using allozyme and epic-PCR markers. The Mediterranean sea has a complex geological and climatic history with transition zones representing areas of exchange resulting in significant biodiversity. While the Strait of Gibraltar opened 5.33 million years ago allowing marine biota to disperse freely into the Mediterranean, present genetic patterns suggest limitations to gene flow for some species. The study analyzes the population structure of solea solea populations from Atlantic and Mediterranean locations to assess gene flow between them. Samples were collected from 11 locations along the Tunisian coast and in Morocco and France totaling 290 individuals.