Types of Coral

Corals come in a wide variety of shapes, sizes and colors and are made up of a rocklike deposit that consists of calcareous skeletons secreted by anthozoans. They are divided into main categories: hard corals, such as brain corals; and soft corals, such as sea plumes. Corals are living marine organisms and each coral head is comprised of a number of identical polyps. Corals can reproduce sexually and through reproduction relocate to new areas.

  1. General Coral Behaviors

    • Corals belong to the Anthozoa class and members of this group have polyps or flower-like structures. Corals have a simple body plan designed for food to pass in and out of the gastrovascular cavity, which is a stomach-like sac with one opening. The polyps feed on various microscopic plankton, tiny fish and small shrimp, using their tentacles to immobilize and kill prey. Once the prey is digested the stomach reopens to eliminate waste and it begins the feeding cycle once again. Corals grow from one founder, dividing repeatedly, so a colony of corals will consist of a base attached to a reef, while on the upper surface there will be hundreds of polyps.

    Brain Coral

    • Brain corals are the common name given to the faviidae family of corals; they are hard corals. They are so named due to a superficial resemblance to an animal brain in terms of spheroid shape and grooved surface. Each coral head is formed by secretion of a skeleton of calcium carbonate making them an important part of coral reef builders. The corals are found in warm water coral reefs around the world. The brain coral can live up to 900 years and grow to heights of six feet or more. At night they extend tentacles to catch their food and use the tentacles as protection during the day.

    Red Carnation Coral

    • Red carnation coral is more commonly referred to as colored cauliflower coral and strawberry coral. The coral is a soft coral type with spicules (small crystal-like structures) embedded in the tissues to provide structural strength. Red carnation coral has a rich red color with many tentacles. Each tentacle is made up of eight polyps. The coral thrive on a diet of plankton, baby shrimp and other small foods suited for invertebrates.

    Purple Acropora Coral

    • The purple acropora coral is a beautiful species of hard coral. It varies in shades of soft to solid purple, a relatively uncommon color for hard corals. The acropora coral has many different species and growth forms; the most common growth form is the bush-like appearance with short, compact branches. Other growth forms include bottle brush, stag horn and table top. Acropora corals receive the majority of their nutrients from photosynthesis, but they also feed on various types of zoo plankton and phyto.

    Sea Pen Coral

    • Sea pen corals belong to the Pennatulacea order of marine corals and there are 14 family groups in this order. They are widely distributed in tropical and temperate waters and are part of the soft corals grouping. For the most part, sea pen corals resemble a bunch of feathers in appearance, but the larger formations do not have the feathery structure. Sea pens have multiple polyps with one polyp losing the feathers and forming into a bulbous root that helps to anchor the coral in place.