which group of marine animals lives mostly in tropical waters? weegy
P. 1  Pilchard or Sardine: a small, oily fish that typically swims in large schools. 2  Plankton: tiny marine organisms of all kindsâanimals, plants, bacteria, algae, protistsâthat play a major role in the worldâs food chains and chemical cycles. 3  Porcupine Fish: a spiny tropical marine fish that can inflate itself.