Scientists in central Japan have discovered three new species of bioluminescent worms that are eerily reminiscent of creatures from Japanese folklore. The new Polycirrus worms found in various parts of Japan are named after a famous Japanese marine biologist as well as these supernatural beings.
Bioluminescence occurs by organisms through a chemical reaction known as chemiluminescence. The reaction produces very low heat levels, which is why it is also referred to as “cold light”. Organisms that produce this effect use it for a variety of purposes, particularly attracting potential mates or prey. Other species, such as centipedes and fireflies, use light to ward off predators.
But these bright bioluminescent organisms are extremely rare. Scientists have now found only around 7,000 species of such organisms worldwide, mostly in the ocean. A limited number of studies have been conducted in this area due to the lack of sufficient samples for classification and comparison.
The fact that bioluminescent creatures are so rare makes the discovery of new worms even more important.
“Our previous research on the luminescence of the genus Polycirrus made it a valuable specimen for bioluminescence studies,” said Naoto Jimi, principal investigator at Nagoya University in Japan. We discovered that the thing is actually three different species.”
Polycirrus are small worms that are usually found in shallow waters such as rivers and streams or on the coasts in Japan. These worms are also known for their tentacles, which they use to search for their food. The tentacles emit a bright blue-violet glow, giving the worms an interesting, expressive appearance.
This is why Jimi and his team decided to name two of the three newly discovered species after entities from Japanese folklore. One of the worms was named Polycirrus onibi, after a type of willful yokai (Japanese spirit being), called onibi (demon fire), believed to drive travelers in remote areas to their death.
Another is the Polycirrus aoandon, or blue lantern, named after a ghostly yokai that appears as an evil woman wearing a white kimono with horns and sharp teeth. This yokai haunts lanterns and turns their flames blue.
The last worm, Polycirrus ikeguchii, is named after Shinichiro Ikeguchi, the former manager of Notojima Aquarium.
The researchers now aim to learn how the newly discovered worms produce their glow. They hope their findings will deepen our understanding of the molecular processes involved in bioluminescence and may have an impact on the development of new technologies.
The study was published in the Royal Society Open Science.