Broccoli Coral

Litophyton arboreum, or broccoli coral, is a widespread soft coral species found in the 🌊 Red Sea through to the Western Pacific. It typically grows up to 80 cm and is commonly seen on reef slopes or hard substrates. The coloration of Litophyton arboreum varies, ranging from pale olive-green to yellow or grey. This species belongs to the anthozoans in the order Alcyonacea, within the family Nephtheidae. Initially classified by Peter Forsskål in 1775, the entire genus Litophyton underwent reclassification in 2016 based on phylogenetic data, in contrast to its original morphological classification.

In the 🌊 Red Sea, Litophyton arboreum is commonly found. A reef transect study conducted in 1997 revealed that octocorals, including Litophyton arboreum, account for less than 20% of soft coral coverage on reef flats and upper fore-reefs in the Gulf of Eilat off the East coast of the Sinai Peninsula. The dominant octocorals in this area are typically represented by a few species forming carpet-like colonies. Litophyton arboreum, although not usually a dominant octocoral, can make up to 36% of living soft coral coverage in the Gulf of Eilat Nature Reserve. In other locations within the 🌊 Red Sea, such as the South and Center Muqebla regions, Litophyton arboreum may only compose around 3% of the soft coral coverage.

The settlement space available on the reef, along with physical factors like wave action, temperature fluctuations, salinity, and light, as well as biological factors such as competition, predation, and disease, play crucial roles in limiting the success and prevalence of Litophyton arboreum colonies. Predation and competition for space can disrupt the continuous growth of 🌊 Red Sea soft coral communities, resulting in patchy distributions across the reef. However, the coexistence of stony corals, soft corals, and algae in the Gulf of Eilat indicates that no single component has distinct competitive dominance. Instead, different species exhibit competitive dominance in various locations based on their unique ecological niches. The competitive hierarchy of Litophyton arboreum within and between other coral species is currently unknown.

In some areas, like the Gulf of Aqaba off the 🇯🇴 Jordanian coast, Litophyton arboreum is found in well-developed reefs. These reefs in the Gulf of Aqaba lack spur and groove patterns on the fore-reef, which is likely due to the relatively calm waters of the area. The absence of significant wind and wave action eliminates the necessary force for the formation of spur and groove structures. The Aqaba reefs are biogenic in origin, similar to the majority of reefs worldwide, and are well-developed around capes. These capes are distinct and separated by sandy embayments that correspond to past dried river beds. Additionally, shallow bays containing seagrass beds fringe the Aqaba reefs, leading into the reefs themselves. The reefs feature wide, built coral formations, most abundant at a depth of 20 meters, with reef flats being most prevalent at 60 meters. The spatial distribution of corals in the Aqaba community suggests that ecological succession, primarily driven by geological and ecological forces, shapes the topography of the reef. The existing Aqaba reefs exhibit high diversity, but their further expansion is constrained by steep shelf inclines. Given the benthic topography of the existing reefs, major reef expansion in this area is highly unlikely.

Similar to other marine organisms dwelling on reefs, Litophyton arboreum possesses potential applications in the medical field, many of which remain undiscovered. A study conducted in 2006 demonstrated that 83% of Alcyonacean corals in the 🌊 Red Sea exhibit antimicrobial activity against various marine bacteria found in the surrounding environment. As a defense mechanism against microbial attacks, 🌊 Red Sea Alcyonacean corals employ antibiotic compounds. In 2018, a specific study conducted on Litophyton arboreum successfully identified and isolated a pseudoguaiane-type sesquiterpene compound called litopharbol. This organic molecule exhibits both antimicrobial and anticancer activities, showcasing direct implications for medicinal applications.