Japan has a lot of uninhabited islands, about 158 of which the government named in 2014 to ensure that the water around them continues to belong to Japan.

But now, one of those islets has disappeared, Japanese newspaper Asahi Shimbun reported this week. And no one seemed to notice until now.

Japan Coast Guard patrol boats approach a Chinese fishing boat, left, in 2013, off the northeastern coast of Miyako island, about 200 kilometres southwest of the disputed islands, called Senkaku in Japan and Diaoyu in China. Credit:AP

The Japanese Coast Guard is apparently planning to search for the islet, called Esanbehanakitakojima, about one-third of a mile away from Sarufutsu, a village on Hokkaido island.

Hiroshi Shimizu, an author who published a picture book about Japanese islands, was the one who reported that the islet wasn't where it's supposed to be. He wanted to visit Esanbehanakitakojima as part of a follow-up book project, but the Japanese newspaper reported that he just couldn't find it. That's when he reached out to Sarufutsu's village fishery to ask where it might be.