Cyclomedusa

 is an organism in Happy Birthdays.

Birth Requirements
For to appear in the cube, there needs to be a large amount of Stromatolite along with a fairly high cube temperature and some area of Sea. It can take some time for Cyclomedusa to appear due to not having a a true ancestor. Using a Seed of Life on Stromatolite will reduce the amount of time for it to appear. After a bit of time with these conditions, Cyclomedusa should appear. During the story mode, it becomes available during the first episode: The Cube is born.

Trivia

 * Cyclomedusa is depicted as a jellyfish in the game, but in real life, Cyclomedusa was originally thought to be a jellyfish but some specimens seem to be distorted to accommodate adjacent specimens on the substrate, apparently indicating a benthic (bottom-dwelling) creature.