Often known as the carnation corals, all of the species within the genus Dendronephthya feature funky tree-like structures that make them a popular choice for home aquarists. Recent research studying the corals' close relatives, the anemones, suggests that corals transform certain sunscreen chemicals into potent toxins. When a coral encounters a chemical like oxybenzone it recognizes it as a foreign molecule. In an attempt to remove the chemical, corals attach a sugar to the oxybenzone, but this act actually turns it into a sun magnifier. The newly transformed chemical now amplifies the sun's UV rays and effectively bakes the symbiotic algae, causing the corals to bleach. As a soft coral, it does not produce a hard shell of calcium carbonate. However, the Venus sea fan coral can hold itself upright in the current, growing to a height of about 6.6 ft (2 m) with relative ease.

Most great star corals will form massive domes that look green, red, or brown in color. However, there are actually two morphs of this species, diurnal and nocturnal. So, the diurnal morphs, which tend to be brown, have polyps that expand and feed during the day and night. The nocturnal morph is usually brightly colored and it expands only at night to feed.Coral reefs are some of the most biodiverse places on Earth, and their loss could have severe consequences for coastal communities and industries such as tourism and fishing. Corals are related to sea anemones, and they all share the same simple structure, the polyp. The polyp is like a tin can open at just one end: the open end has a mouth surrounded by a ring of tentacles. The tentacles have stinging cells, called nematocysts, that allow the coral polyp to capture small organisms that swim too close. Inside the body of the polyp are digestive and reproductive tissues. Corals differ from sea anemones in their production of a mineral skeleton. There are 2 main classifications for corals: 1. Hard coral (scleractinian and stony coral) [13] which form reefs by a calcium carbonate base, with polyps with 6 stiff tentacles, [14] and 2. Soft coral (Alcyonacea and ahermatypic coral) [13] which are pliable and formed by a colony of polyps with 8 feather-like tentacles. [14]These two classifications arose from differentiation in gene expressions in their branch tips [12] and bases that arose through developmental signaling pathways such as Hox, Hedgehog, Wnt, BMP etc. Whether you’re a keen scuba diver or simply an ocean lover, chances are pretty high that you’ve marveled at the wonders of the world’s colorful coral reefs at some point in your life. Presently, corals are classified as species of animals within the sub-classes Hexacorallia and Octocorallia of the class Anthozoa in the phylum Cnidaria. [8] Hexacorallia includes the stony corals and these groups have polyps that generally have a 6-fold symmetry. Octocorallia includes blue coral and soft corals and species of Octocorallia have polyps with an eightfold symmetry, each polyp having eight tentacles and eight mesenteries. The group of corals is paraphyletic because the sea anemones are also in the sub-class Hexacorallia.

Furthermore, the clubbed finger coral is one of the few corals that’s not currently at risk of extinction. It has a fairly widespread distribution, though some populations, particularly around the US Virgin Islands have been damaged by bleaching and disease in recent years. 15. Smooth Cauliflower Coral ( Stylophora pistillata) So, when given enough sunlight, most vase coral can survive off the zooxanthellae’s photosynthesis alone. 7. Venus Sea Fan Coral ( Gorgonia flabellum) One of the best-known types of soft coral, the Venus sea fan tends to form massive fan-like structures that grow vertically upward from the ocean floor. It is known that the coral's microbiome and symbiont influence host health, however, the historic influence of each member on others is not well understood. Scleractinian corals have been diversifying for longer than many other symbiotic systems, and their microbiomes are known to be partially species-specific. [74] It has been suggested that Endozoicomonas, a commonly highly abundant bacterium in corals, has exhibited codiversification with its host. [75] [76] This hints at an intricate set of relationships between the members of the coral holobiont that have been developing as evolution of these members occurs. Groove brain corals can grow to be about 6 feet (1.8 m) in diameter. They usually take on a circular shape but, while it might look like there is just one giant groove brain coral, these animals like to grow in groups of multiple individuals. So, what you see as a single specimen is often a small colony.Essentially, coral bleaching is a process that happens when coral gets stressed out. Of course, coral doesn’t get stressed out by its math homework like we humans might, but it does become stressed out when there are major changes in its environment. Jones, O.A.; Endean, R. (1973). Biology and Geology of Coral Reefs. New York, US: Harcourt Brace Jovanovich. pp.205–45. ISBN 978-0-12-389602-5.

When organ pipe coral dies, it often leaves behind a skeleton of calcium carbonate. This skeleton can be bright red, which makes it particularly attractive to scuba divers who come across it. Corals can be both gonochoristic (unisexual) and hermaphroditic, each of which can reproduce sexually and asexually. Reproduction also allows coral to settle in new areas. Reproduction is coordinated by chemical communication. [ clarify] Sexual [ edit ] Life cycles of broadcasters and broodersa b US Department of Commerce, National Oceanic and Atmospheric Administration. "NOAA's Coral Reef Conservation Program (CRCP) - Coral Facts". coralreef.noaa.gov . Retrieved 2022-04-26. A popular source of coral material for jewelry and other manufactured goods, precious coral refers to the species within the genus Corallium. Thankfully, while the grooved brain coral is susceptible to bleaching and disease, it seems to be fairly resilient. Furthermore, it is still somewhat common throughout its range and the IUCN lists the grooved brain coral as a species of least concern. 12. Boulder Star Coral ( Monstastrea annularis/ Orbicella annularis) The common mushroom coral forms small oval shapes that look a whole lot like your standard wild mushroom. They prefer to live in mostly quiet reefs with relatively little activity. In fact, they don’t form colonies like many of the other corals in Hawai’i. However, adaptation to climate change has been demonstrated in many cases, which is usually due to a shift in coral and zooxanthellae genotypes. These shifts in allele frequency have progressed toward more tolerant types of zooxanthellae. [114] Scientists found that a certain scleractinian zooxanthella is becoming more common where sea temperature is high. [115] [116] Symbionts able to tolerate warmer water seem to photosynthesise more slowly, implying an evolutionary trade-off. [116]