Some animals are so FUGLY that they don't even look like animals. The sea apple often looks more like a badly diseased potato. The sea apple is actually related to the gentle sea cucumber.
Sea apples are filter feeders, using their tentacles to capture plankton from the water around them. They have tube-like feet to move about and to attach themselves to reefs and rocks. They can grow to be almost eight inches around.
Though sea apples are sold commercially for aquariums, they rarely do well. They are likely to starve to death due to a lack of plankton in levels appropriate for the animal. Other aquarium inhabitants are also likely to pick on sea apples by nipping at their tentacles.
When stressed by this kind of treatment, sea apples can release a toxin into the water, killing the other creatures in the aquariums. They can also expel their internal organs suddenly to scare off predators.