marine reef biome marine subtidal rocky reef biome 2010-03-15T11:27:06Z ENVO ENVO:01000050 ORCID:0000-0002-4366-3088 The marine rocky subtidal reef biome comprises regions of the marine reef biome composed mainly of rock and which harbour abundant communities of algae and invertebrates. These reefs are often very patchy, with alterations of rocks dominated by rich invertebrate assemblages and turf-forming calcareous red algae.