<0.1% of earth's upper oceans: ~25% of the globe's marine species %
||Blackall LL, Wilson B, van Oppen MJ. Coral-the world's most diverse symbiotic ecosystem. Mol Ecol. 2015 Nov24(21):5330-47. doi: 10.1111/mec.13400 p.5330 right column bottom paragraphPubMed ID26414414
||Spalding MD, Ravilious C, Green EP (2001) World Atlas of Coral Reefs. University of California Press, Berkeley.
||P.5330 right column bottom paragraph: "Coral reefs are built by scleractinian or hermatypic (stony) coral animals in nutrient depleted marine waters and, although they occupy <0.1% of earth's upper oceans, they provide the habitat for ~25% of the globe's marine species (primary source). There are numerous macroorganisms with varying degrees of association with corals including crabs and other crustaceans, worms, sponges, bivalves and hydrozoans, fishes, sea urchins, octopuses and sea stars."