World’s Rarest Deepwater Shark Swims with Diver off Komodo Island, Indonesia [Video]

A pair of divers , Penny Beilich and Heikki Innanen, on Indonesia's Komodo Island had a once-in-a-lifetime encounter this week when they crossed paths with a rarely seen megamouth shark. 

The diver was exploring the northernmost string of the islands known as Gili Lawa Laut, a popular diving spot for tourists when the shark happened to swim by.

Video shows a clear image of the shark gently gliding through the water. It's characteristic head and mouth get within close proximity of the diver before it turns and swims away.

"The [shark] seemed in good health, and a little bit interested to see us down there," Innanen said to Earth Touch. "It adjusted its course to straight at us and then passed around three meters away. We were only in water about eight metres deep at the time."

According to National Geographic, The Florida Museum of Natural History keeps an official list of megamouth shark sightings dating back to its discovery in 1976. In the past 41 years, just over 60 sightings have been confirmed. The big fish are believed to grow roughly 17 feet (5 metres) long.

The bizarre sharks were first discovered in 1976 and were considered so strange at the time that scientists categorised them in a brand new genus and family.

While the species is mysterious, megamouth sharks present little threat to people. Despite their impressive size, megamouth sharks (Megachasma pelagios) feed on some of the ocean's smallest inhabitants. 

They swim with their huge mouths open to feed, filtering their meals through the inner lining of their gills. Its chief prey is shrimp-like krill, jellies, and other plankton.

"The biology of the megamouth is almost unknown," says Dr Kazuhiro Nakaya, a professor emeritus at Hokkaido University who has done extensive work on megamouth sharks. "I can't say this is normal or not. However, it swims strongly and beautifully, and I feel this is their normal behavior. So beautiful and impressive."

Dr Dave Ebert, who also studies these creatures confirms that it appears healthy. "It looks like it is swimming just fine to me," he says. "An amazing sighting!"

According to Earth Touch, the clip is among the first natural swimming scenes ever captured of a megamouth at sea - the first without nets in vicinity. 

Megamouth sharks have been spotted primarily near Japan and Taiwan, but sightings have occurred in the Atlantic, Pacific, and Indian Oceans.