In 1872, part of a damaged whale mandible and set of teeth were found on Pitt Island in New Zealand. Initially thought to be bones from the Scamperdown whale, also known as Gray’s beaked whale, it was not until 1874 that John Edward Gray—who had discovered the Gray’s beaked whale—examined the bones and assigned them to a new, never-before-seen species.

Debates among zoologists couldn’t pin down the name or classification of this new species. In the 1950s, a damaged skullcap was found on New Zealand’s White Island, and was assigned to many different species, later including the Bahamonde’s beaked whale (which was known from a damaged skull found in 1986 on Robinson Crusoe Island in Chile). It was not until 2002 that researchers matched the mandible and teeth from Pitt Island to the skulls from White Island and Robinson Crusoe Island, naming it the spade-toothed beaked whale, Mesoplodon traversii. Yet beyond those three bone fragments, nobody knew what it looked like, or really anything about it.

Then, in December of 2010, two whales—an adult female and a male calf—beached themselves on Opape Beach in the Bay of Plenty, New Zealand. They were initially categorized as Gray’s beaked whales, an echo of the situation upon the discovery in 1872. Further DNA research, however, identified these two whales as spade-toothed beaked whales, the first complete specimens ever seen.

Scientific American

How this species managed to avoid human eyes for so many years is unknown, but this is the first step toward learning more about the world’s rarest species of whale. The skeletal remains of the whales are now being kept at the Museum of New Zealand Te Papa Tongarewa.