The term 'brilliantly colored marine fish' can be summarized as a WRASSE, which is a type of fish found in the ocean. Wrasses are known for their bright colors and are found in tropical and subtropical waters around the world. They are typically small to medium-sized fish, with some species reaching up to two feet in length. Wrasses are carnivorous and feed on small invertebrates such as crustaceans and mollusks. They are also popular among aquarium hobbyists due to their vibrant colors and active behavior.