Résumé:
In ecology, the study of patterns between species is necessary to understand the factors affecting their distribution and the dislocations causing their divergence. The aim of this work is to study the phylogeny and the phylogeography of some Prosobranchia Gastropoda (Patella rustica and Patella ferruginea) to understand the pattern of connectivity between populations by explaining the causes of their differences, their distribution and their responses to environmental change using the paleontological data. After identifying our species morphologically, we performed the molecular work (DNA extraction, PCR, DNA sequencing ...) using the mitochondrial marker cytochrome oxydase I (COI). The results of mitochondrial DNA sequences obtained were treated using some software (Codon Code Align, MEGA 5…) following the method of maximum likelihood "ML". We noted that the divergence and geographic distribution among species was consistent with some paleontological changes, which could be the cause of differences of the studied species.
