Acropora

Acropora is a genus of small polyp stony coral in the phylum Cnidaria. Some of its species are known as table coral, elkhorn coral, and staghorn coral. Over 149 species are described. Acropora species are some of the major reef corals responsible for building the immense calcium carbonate substructure that supports the thin living skin of a reef. Depending on the species and location, Acropora species may grow as plates or slender or broad branches. Like other corals, Acropora corals are colonies of individual polyps, which are about 2 mm across and share tissue and a nerve net. The polyps can withdraw back into the coral in response to movement or disturbance by potential predators, but when undisturbed, they protrude slightly. The polyps typically extend further at night to help capture plankton and organic matter from the water. The species are distributed in the Indo-Pacific (over 100 species) and Caribbean (3 species). However, the true number of species is unknown: firstly, the validity of many of these species is questioned as some have been shown to represent hybrids, for example Acropora prolifera; and secondly, some species have been shown to represent cryptic species complexes. Symbiodinium, symbiotic algae, live in the corals' cells and produce energy for the animals through photosynthesis. Environmental destruction has led to a dwindling of populations of Acropora, along with other coral species. Acropora is especially susceptible to bleaching when stressed. Bleaching is due to the loss of the coral's zooxanthellae, which are a golden-brown color. Bleached corals are stark white and may die if new Symbiodinium cells cannot be assimilated. Common causes of bleaching and coral death include pollution, abnormally warm water temperatures, increased ocean acidification, sedimentation, and eutrophication. In 2014 the U.S. Fish and Wildlife Service listed ten Acropora species as 'threatened'. Most Acropora species are brown or green, but a few are brightly colored, and those rare corals are prized by aquarists.

Responses of reef bioindicators to recent temperature anomalies in distinct areas of the North Ari and Rasdhoo atolls (Maldives)

Arthur Adams, Aurélie Angéloz, Anaël Lehmann

Assessments of reef sediments in the North Ari Atoll (Maldives) were conducted in 2015 and 2018 on reefs of three islands with different management strategies: community, resort, and uninhabited. Indices applied were the Foraminifera in Reef Assessment and ...

2020

Positive interactions between corals and damselfish increase coral resistance to temperature stress

Responses of reef bioindicators to recent temperature anomalies in distinct areas of the North Ari and Rasdhoo atolls (Maldives)

Responses of reef bioindicators to recent temperature anomalies in distinct areas of the North Ari and Rasdhoo atolls (Maldives)

Positive interactions between corals and damselfish increase coral resistance to temperature stress