Meet a fish that's all mouth ... but incredibly tough too! The male sarcastic fringehead, or what we call the "alien fish," is only about 20cm long. But don't let that fool you. It skillfully uses its large mouth to intimidate all rivals and intruders, even divers, to protect its humble shell. During mating season, it uses a combination of romance and rough behavior to lure and then kick out its mate after she's laid her eggs. It then becomes a loving and protective father until the fry hatch.