The Great Star coral or scientifically known under the name of Montastraea cavernosa, is a species belonging to the family Montastaeidae within the order Scleractinia. Specimens of this species are found in the tropical waters of the Atlantic Ocean, along the western coasts of Africa and the eastern coasts of America. Although it is possible to find it up to 120 meters depth, it is up to 30 meters depth where it is more frequent to find this species, generally associated with reef environments.
Montastraea cavernosa is a colonial coral with a massive calcareous skeleton. The colonies are usually not very large and can reach up to 50 cm in length. Normally, the shape of the colonies is somewhat conical and longer in length than in width. Each of the polyps that make up the colony is located in a conical calyx of approximately 0.5 cm in diameter and clearly separated from the rest of the calyxes. The polyps are fleshy in appearance, and both during the day and at night will fully deploy their tentacles to search for prey.
Inside the tissue of Montastraea cavernosa we find zooxanthellae algae that perform photosynthesis. As a result of this activity, sugars and oxygen are generated and used by the colony as a source of energy. Between 95 and 70% of the energy consumption of the colony will be supported by this energy contribution obtained from the zooxanthellae. The rest of the caloric intake is obtained by trapping plankton and organic matter carried by currents, thanks to the stinging tentacles of the polyps. It is possible to find a wide repertoire of colors in the individuals of this coral species.
They reproduce asexually by budding, and sexually by releasing their sex cells to the outside. Montastraea cavernosa forms male or female colonies, with the environmental conditions determining the sex. In this type of reproduction, corals release eggs and sperm into the water between July and October, thus fertilization is external. The eggs, once outside, remain drifting in the currents for several days, later a planula larva is formed, which falls to the bottom, adheres to it and begins its sessile life, secreting calcium carbonate to form a skeleton. Subsequently, it reproduces by gemmation, thus forming the coral colony.Photos: