Antipathidae Family of Hexacorals

One Hexacoral of the Antipathidae Family can be found in this website:

Galapagos Black Coral, Antipathes galapagensis. A representative of the Antipathidae Family of Corals.

Phylogeny:   Hexacorals of the Antipathidae Family,  like Jellyfish, and Hydroids,  belong to the phylum Cnidaria. They are in the class Hexacorallia and the order Antipatheria. The Antipathidae Family is one of eight families in this order. The Antipathidae Family is fairly large, with nine genera and one hundred twenty species. Species in this family are also commonly called Antipatharians.

Morphology: Black Coral polyps have radial symmetry, a hollow digestive cavity, and specialized stinging structures contained within the tentacles surrounding the mouth. Their polyps have a flower-like appearance, representative of the class Anthozoa. Because the tentacles are tiny, they may have a fuzzy appearance when extended. The polyps cannot fully retract into the skeleton as stony corals can. The skeleton gives the colony its structure and is made of chitin and protein. The skeleton may be unbranched and straight  or coiled, or it may be branched and bushy or fan-like. The polyps may be arranged in single rows or irregular rows along the branches. The branches are often covered with small conical or triangular spines. The branches are usually black or dark brown in color. Corals in this family are slow-growing. Those in more protected waters grow tallest. Colonies can range from 5.0 cm (2.9 inches) to 3 m (10 feet) in height.

Habitat and Distribution: Black Coral is generally found attached to coral, rock, wreckage, and other hard substrates, but some can be found on soft substrates. Many species live in relatively shallow waters, starting at around 15 m (49 feet), and some reach depths of 6,098 m (20,000 feet). Black Corals are found worldwide in subtropical to tropical seas. Five species from this family are found in Mexican waters.

Reproduction: Galapagos Black Corals are gonochoric (male or female for life), both at the polyp and colony levels. Reproduction can be asexual, through budding, or sexual. Sexual reproduction involves broadcast spawning, with external fertilization. The fertilized eggs become planktonic larva.

Ecosystem Roles:  Black Corals are suspension feeders, using their tentacles to filter zooplankton from the surrounding water. Most black Corals are located in areas of strong current. This increases the amount of plankton-rich water that passes over their tentacles. Black Corals are azooxanthellate. In turn they are preyed upobm by decapods, fish, gastropods, and the Green Sea Turtle, Chelonia mydas. Predation does not seem to significantly impact Black Coral growth. Black Corals often host fish, shrimp, and zoanthids in commensal relationships.