In this picture released by Awashima Marine Park, a 1.6 meter long Frill shark swims in a tank after being found by a fisherman at a bay in Numazu, Japan. The frill shark, usually lives in waters 600 meters deep. It's body shape and it's number of gills are similar to fossils of sharks which lived 350,000,000 years ago. In relation to it's size and 300 teeth, the frill shark is usually referred to as a sea serpent or Loch Ness Monster.
"The endangered dugong is the only southern African sea cow. This ancient order (Sirenia) is distantly related to elephants and also includes the West African and tropical American manatees. Dugongs are slow-moving, entirely aquatic creatures of sheltered tropical waters, where they graze seagrass beds with the rising tide." www.bradtguides.com
mudskippers - fish that have evolved to live out of water. These fish are completely amphibious, and use their pectoral fins to walk around on land. They have a large gill chamber that retains water and closes tightly when they are not immersed in water.
Weighing in at over five tons and measuring up to 33 feet long, basking sharks are the second largest sharks in the ocean (after whale sharks). These gentle giants troll through the water with their cavernous mouths wide open, using 5,000 gill rakers to filter plankton out of 1.5 million liters of water every hour. [article: 10 most bizarre looking sharks on earth]
Snowflake Moray, Kona, Hawaii by SteveD.: The snowflake moray eel (Echidna nebulosa) has white, black and yellow splotches all over its body, which come together to look like snowflake designs. Moray eels eat their prey in a unique way – with two jaws. The second set of jaws is in their throat, which shoots up and grabs the prey from the main pair of jaws, drawing the prey down to the esophagus. http://ocean.si.edu/ocean-photos/snowflake-moray-eel #Moray_Eel