I recently caught a Mareanie, and I saw it had an attack animation where turns upside down and strikes with the "tentacles" that covers its body. What kind of sea creature can do something similar? :(
It is based on crown-of-thorns starfish and sea urchins. More evidence of the crown-of-thorns starfish origin is through how it feasts on Corsola, and real life crown-of-thorns feast on polyps of coral reefs. Another connection is how Mareanie’s appendages grow back quickly, much like starfish.
Source: https://m.bulbapedia.bulbagarden.net/wiki/Mareanie_(Pokémon)