A tiny new clione species found in Toyama Bay, off Toyama Prefecture, swims in the water. (Provided by the Shellfish Museum of Rankoshi and University of Toyama)

TOYAMA--A new species of clione, commonly known as an “angel in drift ice,” was discovered in the waters of Toyama Bay here, northwestern Japan, a Japanese university team announced Oct. 12.

There is a possibility that it is endemic to the Sea of Japan, according to the team led by Zhang Jing, 50, professor of chemical oceanography at the Graduate School of Science and Engineering for Research of the University of Toyama.

In August 2016, about 30 tiny cliones were caught in a net that was cast out to catch plankton in a field trip conducted in Toyama Bay. They measured between 0.5 millimeters to 5 mm.

Clione expert Tomoyasu Yamazaki, 34, the director of the Shellfish Museum of Rankoshi in Hokkaido, conducted DNA tests on the mysterious shell-less conch, and concluded it is a new species.

Cliones are a variety of shell-less conch, and the new sea slug becomes the fifth known species of its kind.

The discovery came only a year after Yamazaki and his fellow researchers identified the fourth species of clione in 2016, almost 100 years after the identification of the last one.

“I never imagined there would be a new species of clione in Toyama Bay,” said Zhang.

Cliones are known to prefer cold water and, in the proximity of Japan, they were only known to inhabit the Sea of Okhotsk, northeast of Hokkaido.

The new species will be named and then are expected to be displayed at the city-run Uozu Aquarium in Uozu, Toyama Prefecture, as well as the shellfish museum in Rankoshi, Hokkaido.