Etude démographique de l’espèce Cymbula safiana (Lamarck, 1819) au niveau de la côte de la baie de Mostaganem

Abstract

A demographic study on the species Cymbula safiana (Lamarck, 1819) was carried out at one station on the coast of Mostaganem. This work made it possible to report C. safiana in a new station (Sidi Medjdoub) and to identify some plant species such as Ellisolandia elongata and Lithophyllum incrustances and Ulva lactuca as well as some species of animals [Amphipod Crustaceans (Gammariens and Caprelians) and Bivalve Mollusc (Mytilus galloprpvincialis) and a Polyplacophore (Chiton sp)] living on its shell. This study confirmed that the presence of C. safiana is related to several environmental factors : smooth substrate with steep slope associated with Lithophyllum incrustens in an area with high hydrodynamics far from anthropogenic activity. In addition, C. safiana must arouse the interest of local authorities since the texts protecting it are not applied and the species still suffers from illegal collection. It is essential to protect this species since it has an important ecological role.