Patterns of diversity of the north-eastern Atlantic blenniid fish fauna (Pisces: Blenniidae)

This paper presents an analysis of the distributional patterns of blenniids (Pisces: Blenniidae) in the north-eastern Atlantic. Two peaks of species diversity were found, both in terms of number of species and number of endemics: one in the tropical African coast and another in the Mediterranean Sea. A cluster analysis of similarity values (Jaccard coefficient) among the eastern Atlantic zoogeographical areas, revealed the following groups: a north temperate group, a tropical group formed by the tropical African coast and Mauritania, another group formed by the islands of Cape Verde, a south temperate group (South Africa), and a southern Atlantic group formed by the islands of Ascension and St Helena. Within the north temperate group, the subgroups with higher similarities were: Azores and Madeira, Canary Islands and Morocco, and the Mediterranean and the Atlantic coast of the Iberian Peninsula. Based on affinity indices, the probable directions of faunal flows were inferred. The tropical coast of Africa and the Mediterranean emerged from this analysis as probable speciation centres of the north-eastern Atlantic blenniid fauna. The Mediterranean may have also acted as a refuge during glacial periods.