Shallow epibenthic communities of Ilha do Sal (Cape Verde Archipelago, Eastern Atlantic)

Epibenthic communities were studied by snorkelling and SCUBA diving down to 33 m depth at Sal, the island at the northeastern corner of the Cape Verde Archipelago, in the winter of 1990-1991. Apart from minor differences related to exposure, three main bionomic zones were identified: 1) the littoral, with littorinids, chthamalids and encrusting corallines; 2) the shallow sublittoral, with corals and algae; 3) the sublittoral below 20 m depth, with gorgonians and antipatharians. The first, and perhaps the third. showed a prevalent Atlantic-Mediterranean affinity, the second a pronounced tropical West Atlantic affinity. This possibly reflects the influence of distinct water layers, thus suggesting that a bionomic approach might help in the analysis of the composite biogeographic character of the Cape Verde marine biota. However, both bionomic and biogeographic studies suffer badly from a persistent lack of sufficient taxonomic knowledge.