The tropical waters of Australia's coral reefs are home to an extraordinary number of marine species. The Great Barrier Reef alone supports an estimated 1,500 fish species. The Orangefin Anemonefish featured on the stamp and medallion is one such species. It belongs to the family Perciformes and lives among the tentacles of anemones. Anemonefish have a unique ability to produce a skin secretion that mimics a chemical substance produced by anemones to stop the tentacles stinging themselves. This allows the fish to dwell among the tentacles, where it benefits from anemones' robust defence system.