A momentous event took place in Toba Aquarium on 26 May, when the keeper of the facility’s five giant isopods discovered fecal matter in their tank. This would be the first time since April of 2018 that even a trace of poop had been found.

Giant isopods are relatives of those bugs kids around the world play with by poking with a stick so that they curl up into a ball. Pill-bug, potato-bug, roly-poly, or doodle bug are among these things’ many common names, and a fun fact about them is that they are among the very few crustaceans that live on land.
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This time it resulted in a much happier ending for the five isopods which were introduced to the facility in Toba City, Mie Prefecture, in 2013. Moreover, the feces was found to contain scales of a fish not served by the aquarium.

This means that the food which went into making this poop must have been consumed over seven years ago, before they came to the aquarium. While it isn’t clear exactly which isopod dropped the deuce, the finding is a breakthrough in the field of giant isopod regularity, and will hopefully trigger more detailed research into the subject.

https://soranews24.com/2020/05/29/giant-undersea-bug-in-toba-aquarium-poops-for-first-time-in-two-years/