The order Corallinales sensu lato (Rhodophyta) in the Iberian Atlantic: current state of knowledge

Abstract

A review of the order Corallinales sensu lato in the Atlantic Iberian Peninsula is presented with the aim of assessing its current state of knowledge in comparison with adjacent areas (British Isles-Atlantic France, Macaronesia and Iberian Mediterranean). According to the information compiled from more than 250 publications, herbarium data and manuscripts, we concluded that Atlantic Iberian coralline algae have been poorly studied, which resulted in only 49 species reported. By contrast, Macaronesia is the most species-rich region (91), followed by Spanish Mediterranean (67) and the British Isles-Atlantic France (61). In the Atlantic Iberian Peninsula, 17 species occurred commonly (present in more than 50% of the coastline), particularly those corresponding to the genera Amphiroa, Jania, Lithophyllum, Mesophyllum, and Phymatolithon. Instead, the genera Harveylithon, Hydrolithon, Leptophytum, Lithothamnion, Neogoniolithon and Pneophyllum have been occasionally reported. In the Atlantic Iberian Peninsula and adjacent regions, the epilithic growth-form was dominant, followed by the epiphytic, epizoic and the unattached (maerl/rodoliths); besides, sciaphilous taxa were more abundant than photophilous species. The low intertidal and shallow subtidal harbour a high diversity of coralline algae, as well as semi-exposed coasts or areas affected by currents. The present study confirms that studies on the Atlantic Iberian coralline algae are scarce, and that further research on this group is required.