This might be a relative of our pill bugs? But there is probably a lot more evolution between them than between, e.g., horses and sharks. Which, by the way, is also bigger than between bony fish and sharks.
I've always been fascinated by pill bugs, also known as "Armadillidiidae" [1] they are such cool creatures. I don't know why, but the fact that they are land-dwelling crustaceans was just interesting to me.
I had no idea something like this size and related existed in the sea! Incredible! I wonder now what the evolutionary tree looks like.
Isopoda is an Order. This is in family Cirolanidae, so it has much smaller cousins in each beach.
It seems there is an opportunity here, crouching like a cat, to dedicate one of this new species to Hayao Miyazaki. Bathynomus ohmu seems an pretty convenient name also. Maybe the next.