Acropora is a genus of scleractinian coral in the Phylum Cnidaria, also known as table coral, elkhorn coral, or staghorn coral.
Anatomy and distribution
Depending on the species and location,
Acropora may grow as plates or slender or broad branches. Like other corals,
Acropora corals are colonies of individuals known as 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 possible predators, but when undisturbed they protrude slightly. The polyps usually extend further at night as they capture zooplankton from the water.
Acropora is most common in shallow reef environments with bright light and moderate to high water motion. Many small reef fishes live near Acropora colonies and retreat into the thicket of branches if threatened.
Threats
These corals have
zooxanthellae,
symbiotic algae that 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 zooxanthellae cannot be assimilated. Common causes of bleaching and coral death include pollution, abnormally warm water temperatures, increased
ocean acidification, sedimentation, and eutrophication.
Reef-keeping
Most Acropora are brown or green but a few are brightly colored and those rare corals are prized by aquarists. Captive propagation of Acropora is widespread in the reef-keeping community. Given the right conditions, Acropora grows quickly and individual colonies can exceed 1 meter across in the wild. In a well maintained reef aquarium, finger-sized fragments can easily grow into basketball-sized colonies in 1 to 2 years. Captive specimens are steadily undergoing changes due to selection which enable them to thrive in the home aquarium. In some cases, fragments of captive specimens are used to repopulate barren reefs in the wild.
Acropora species are challenging to keep in a home aquarium. They require bright light, stable temperatures, and turbulent water. Providing these elements can be too expensive for the average hobbyist.
References
Reef-keeping Forum
http://www.internationalreefers.com/index.php?
Further reading
Reyes-Bermudez A. et al. 2009. Differential expression of three galaxin-related genes during settlement and metamorphosis in the scleractinian coral
Acropora millepora.
BMC Evolutionary Biology 2009, 9:178.
External links
Category:Anthozoa
Category:Coral reefs
