Sponges vs microbialites: an example from the cryptic biogenic crusts of Aegean submarine caves (Eastern Mediterranean)

Marine cave systems have been acknowledged as ideal natural laboratories to investigate the carbonatogenetic role of microorganisms in confined environments and to clarify how microbial processes develop under stressed conditions. Submarine caves are cryptic habitats characterized by low light intensity, marked oligotrophy and low water circulation. They are colonized by cryptic communities, whose skeletons may form different types of bioconstructions, from small/thin biogenic crusts to large “biostalactites”. These structures are usually strengthened and early lithified by microbialites.