Crescent-tail bigeye fish in the Great Barrier Reef, Australia

© Fred Bavendam/Minden Picture

Sharp vision in the depths. Crescent-tail bigeye fish, Great Barrier Reef, Australia

Say hello to the crescent-tail bigeye, a fish as eye-catching as its name suggests. With large, wide eyes and a distinctive tail shaped like a crescent moon, it's hard to miss. Measuring between 45 and 50 centimetres in length, it has a sleek body and a protruding lower jaw with small conical teeth. Its eyes are adapted to the low-light conditions of deep waters, helping it spot prey and avoid predators. This fish mainly feeds on smaller fish, crustaceans and invertebrates, fuelling its active lifestyle as it patrols reefs in search of food.

You'll usually find these fish near Lizard Island, part of the Great Barrier Reef and reef in the Indo-Pacific region, including the coasts of India, Sri Lanka, the Maldives, Thailand, Malaysia, Indonesia and the Philippines. Named by English navigator Matthew Flinders, the reef stretches more than 1,400 miles. This UNESCO World Heritage Site hosts more than 1,500 species of fish, 400 types of coral and various other marine creatures such as sea turtles and dugongs. So, if you ever go snorkelling in this area, keep an eye out for the crescent-tail bigeye.