Fungia scruposa is a species of mushroom coral that lives a single individual rather than as a colony. It starts out life as a small disk attached to dead coral or rock, but by the time it reaches about 1 inch in diameter, it becomes detached. The adult has a single polyp that reaches up to 10 inches in diameter.
This is the first species of coral that has been observed eating jellyfish. While most of its diet consists of bacteria and mesozooplankton, it does take larger marine life, including the moon jellyfish. F. scruposa feeds at night and its tentacles are withdrawn during the day, leaving the skeleton clearly visible, with the mouth at the center of the disk. The skeleton resembles the gills of a mushroom, hence the common name.
Scientists are not sure how this coral manages to capture jellyfish, but they speculate it may have used its tentacles in the same way some sea anemones feed on other species of jellyfish. It also uses its tentacles to right itself if it is overturned by waves.