Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.
Anthozoa is a subphylum of marine invertebrates which includes the sea anemones, stony corals and soft corals. Adult anthozoans are almost all attached to the seabed, while their larvae can disperse as part of the plankton. The basic unit of the adult is the polyp; this consists of a cylindrical column topped by a disc with a central mouth surrounded by tentacles. Sea anemones are mostly solitary, but the majority of corals are colonial, being formed by the budding of new polyps from an original, founding individual. Colonies are strengthened by calcium carbonate and other materials and take various massive, plate-like, bushy or leafy forms.
Fire corals (Millepora) are a genus of colonial marine organisms that exhibit physical characteristics similar to that of coral. The name coral is somewhat misleading, as fire corals are not true corals but are instead more closely related to Hydra and other hydrozoans, making them hydrocorals. They make up the only genus in the monotypic family Milleporidae.
Elkhorn coral is an important reef-building coral in the Caribbean. The species has a complex structure with many branches which resemble that of elk antlers; hence, the common name. The branching structure creates habitat and shelter for many other reef species. Elkhorn coral is known to grow quickly with an average growth rate of 5 to 10 cm per year. They can reproduce both sexually and asexually, though asexual reproduction is much more common and occurs through a process called fragmentation.
Millepora dichotoma, the net fire coral, is a species of hydrozoan, consisting of a colony of polyps with a calcareous skeleton.
Zoanthus sociatus, commonly known as the green sea mat or button polyp, is a zoanthid usually found in shallow reef zones of tropical regions from Caribbean to southeastern Brazil. Z. sociatus is currently being studied for its use against human lymphatic parasites.
Porites astreoides, commonly known as mustard hill coral or yellow porites, is a colonial species of stony coral in the family Poritidae.
Megabalanus stultus is a species of barnacle first described by Charles Darwin in 1854. It lives on fire corals of the genus Millepora in the Atlantic Ocean from Florida to southern Brazil.
Galaxea fascicularis is a species of colonial stony coral in the family Euphylliidae, commonly known as octopus coral, fluorescence grass coral, galaxy coral among various vernacular names.
Porites lobata, known by the common name lobe coral, is a species of stony coral in the family Poritidae. It is found growing on coral reefs in tropical parts of the Indian and Pacific Oceans.
Millepora alcicornis, or sea ginger, is a species of colonial fire coral with a calcareous skeleton. It is found on shallow water coral reefs in the tropical west Atlantic Ocean. It shows a variety of different morphologies depending on its location. It feeds on plankton and derives part of its energy requirements from microalgae found within its tissues. It is an important member of the reef building community and subject to the same threats as other corals. It can cause painful stings to unwary divers.
Siderastrea radians, also known as the lesser starlet coral or the shallow-water starlet coral, is a stony coral in the family Siderastreidae. It is found in shallow parts of the western Atlantic Ocean as small, solid mounds or encrusting sheets.
Milleporasquarrosa is a species of fire coral that can be found in the Caribbean Sea as well as in the western Atlantic. They are very common on fringing reefs in patches. They have a smooth surface covered in tiny pores from which polyps protrude. They can reach up to 5 centimeters in height and can range from brown or tan in color with slight purple or red tints. It is commonly known as "box fire coral", which refers to its box-like structure and the stinging sensation felt when touched with a bare hand. These corals are important to reef-building.
Millepora platyphylla is a species of fire coral, a type of hydrocoral, in the family Milleporidae. It is also known by the common names blade fire coral and plate fire coral. It forms a calcium carbonate skeleton and has toxic, defensive polyps that sting. It obtains nutrients by consuming plankton and via symbiosis with photosynthetic algae. The species is found from the Red Sea and East Africa to northern Australia and French Polynesia. It plays an important role in reef-building in the Indo-Pacific region. Depending on its environment, it can have a variety of different forms and structures.
Pseudodiploria clivosa, the knobby brain coral, is a colonial species of stony coral in the family Mussidae. It occurs in shallow water in the West Atlantic Ocean and Caribbean Sea.
Dipsastraea speciosa is a species of colonial stony coral in the family Merulinidae. It is found in tropical waters of the Indian and Pacific oceans.
Pseudoplexaura porosa, commonly known as the porous sea rod or the porous false plexaura, is a species of gorgonian-type colonial octocoral in the family Plexauridae. It is native to the Caribbean Sea and the Gulf of Mexico.
Cirrhipathes is a genus of black coral from the family Antipathidae. Coral species in this genus are commonly known as whip or wire corals because they often exhibit a twisted or coiled morphology. In addition to their colorful appearance, with colors ranging from yellow to red passing through blue and green, these species possess a dark skeleton that is characteristic to every black coral.
Agaricia tenuifolia, commonly known as thin leaf lettuce coral, is a species of colonial stony coral in the family Agariciidae. This coral is found in shallow waters in the Caribbean Sea and Gulf of Mexico.
Euphylliidae are known as a family of polyped stony corals under the order Scleractinia.
