Coral
From Memory Alpha, the free Star Trek reference
Coral is a marine organism commonly found in the oceans of Earth. Coral is a type of colony creature, a larger structure composed of multiple individual organisms living in a cooperative manner.
On Earth coral reefs are important marine ecosystems. One of the largest exists off the coast of the former United States of America where the city of Los Angeles collapsed into the sea. (VOY: "Future's End")
In 2269 the coral in the habitat of a Halo fish on the USS Enterprise was affected by spiroid epsilon waves along with all other organic material on board the ship. (TAS: "The Terratin Incident")
