PRETORIA, South Africa — When Pieter Venter went on a recreational deep dive off South Africa's northeast coast in October, he did not expect to come across a living fossil.
"I looked at it carefully and after about six seconds I suddenly realized it was a coelacanth," Venter said recently.
A fish that had been swimming in the seas for some 400 million years, the coelacanth was believed to have been extinct for 70 million years until one was caught by a trawler off South Africa in 1938 and identified by a museum curator.
Venter said he saw three coelacanths on his October dive, 320 feet below the surface. The discovery was made off Sodwana, a bay renowned for its reefs and diving.
It was the first time a diver outside a submersible craft had seen the ancient species in its natural habitat. They have been observed from submersibles off the Comoro Islands, north of Madagascar.
Venter took a team back to verify the discovery and to try to catch them on film.
"The first sighting was like seeing a UFO without taking a photograph," he said.
On Nov. 27, Venter's team found three coelacanths and filmed them at a depth of 350 feet.
The expedition was marred by tragedy as one of the team died after surfacing without proper decompression.
The footage, which was shown to journalists last week, shows three fish ranging in length from 3 to six 6 "standing" on their heads and feeding off the ledge of an underwater canyon.
The coelacanth — known as "old four legs" because of its extra fins — inhabits deep-water caves and canyons, far from the prying eyes of most divers.
The Sodawana fish are the shallowest find so far of the species and the only known population that can be reached by divers.
"This discovery suggests that the coelacanth may be far more widespread than was originally believed, perhaps anywhere where you get these deep canyons and old reefs in tropical waters," said marine biologist Johann Augustyn.
The only other known population — which may be a distinct subspecies — is on the other side of the Indian Ocean, off Indonesia's remote Manado Tua Island.
The Indonesian group only came to light in 1997 when an American marine biologist came across one in a fish market.
Valli Moosa, South Africa's minister for environmental affairs and tourism, told reporters the exact location of the new discovery would be kept under wraps for now and authorities would regulate dives in the area to protect the fish.
"We want no human activity that will cause a disturbance for what is really a very vulnerable species," he said.
The area of the discovery is already a protected marine reserve where fishing on the seabed is prohibited.