Submarine caves of the Salento pensinsula: faunal aspects.

A review has been realized to contribute at the biodiversity assessment of the E.U. habitat “marine submerged caves” in the Salento Peninsula (SE Italy). Information came from the researches explicitly carried out in Salento submarine caves. The number of species recognized (639) is interestingly high notwithstanding the exclusion of plant species (present only at the entrance and not in the dark of the caves) and the limited space available (if compared with neighboring open sea areas). The list includes 385 taxa not present in the extended study of Riedel (1966) on 277 Mediterranean submarine caves. A comparison has also been carried out with the adjacent habitat of the coralligenous assemblage. The high numerical contribution to the species richness of a geographic area is due for sure to the strategy adopted to evaluate species composition of not usual (for caves) assemblages as the plankton or the meiobenthos of rocky walls, but also the inclusion of studies on rarely investigated taxa (as Gastrotricha and Facetotecta). The particularity of the environment, or the geographic position of the Salento peninsula, are probably responsible of the presence of uncommon species (55 new for Italian marine fauna, with 18 new for Science)