Just a tiny update. Yesterday I went kayaking at Miho—about a one-hour drive from my house. As I paddled through the water, I noticed the same jellyfish that I had seen before. And then I saw another.
And another.
It was an overcast day, and since this particular jellyfish is apparently nocturnal, that might have been why there were so many of them.
Did you know that a dead jellyfish can still sting you?1
Apparently, they are called “Andon” jellyfish because of their boxy, lantern-like shape. According to Wikipedia2, an andon is a lamp made of paper stretched over a bamboo frame that became popular in the Edo period.
Here is a link to a YouTube video that appears to be from an aquarium.
If you use DeepL to translate the Japanese caption, it says:
Just as its name suggests, this jellyfish is shaped like an Edo-period lantern.
Although it has a cute appearance, it is highly venomous.
Link to ABC News article: Surfer stung by dead jellyfish’s tentacles, as expert warns venom could last thousands of years
Here is the link to the article: Traditional lighting equipment of Japan