Corals (class Anthozoa), which include sea anemones (order Actiniaria), are gastrovascular marine cnidarians (phylum Cnidaria) existing as small sea anemone-like polyps, typically forming colonies of many individuals. The group includes the important reef builders known as hermatypic corals, found in tropical oceans, and belonging to the subclass Zoantharia of order Scleractinia (formerly Madreporaria). The latter are also known as stony corals in as much as the living tissue thinly covers a skeleton composed of calcium carbonate. A coral "head" is formed of many individual polyps, each polyp only a few millimeters in diameter. The colony of polyps function essentially as a single organism by sharing nutrients via a well developed gastrovascular network, and the polyps are clones, each having the same genetic structure. Each polyp generation grows on the skeletal remains of previous generations, forming a structure that has a shape characteristic of the species, but subject to environmental influences.

Although sea anemones can catch fish and other prey items and corals can catch plankton, they obtain much of their nutrient requirement from symbiotic unicellular dinoflagellates (type of algae) called zooxanthellae. Consequently, they are dependent upon growing in sunlight and for that reason usually found not far beneath the surface, although in clear waters corals can grow at depths of 60 m (200 ft). Other corals, notably the cold-water genus Lophelia, do not have associated algae, and can live in much deeper water, with recent finds as deep as 3000 m. Corals breed by spawning, with many corals of the same species in a region releasing gametes simultaneously over a period of one to several nights around a full moon.

Corals are major contributors to the physical structure of coral reefs that develop only in tropical and subtropical waters. Some corals exist in cold waters, such as off the coast of Norway (north to at least 69° 14.24' N) and the Darwin Mounds off western Scotland. The most extensive development of extant coral reef is the Great Barrier Reef off the coast of Queensland, Australia. Indonesia is home to 581 of the world's 793 known coral reef-building coral species.

More on [ Coral ]

Corals - Twitter Search

Corals and snails arrived from Clearwater FL. All are alive and healthy. Very happy evil bitch now.
distorria (distorria) Thu, 07 Jan 2010 15:32:24 -0000
Corals and snails arrived from Clearwater FL. All are alive and healthy. Very happy evil bitch now.
allergy,, allergy.. doctor,,I'm counting on u.. help this sufferer... euwh all about the corals n sea(bad)weed
Meelkhy (Milka Viona R) Thu, 07 Jan 2010 14:18:17 -0000
allergy,, allergy.. doctor,,I'm counting on u.. help this sufferer... euwh all about the corals n sea(bad)weed
Re: Welcome to MRK - My Coral Farm: WELCOME!!! Great concept and some nice looking corals. Will be checking it out... http://bit.ly/6vDBiK
TheModernReef (Adam Jenkins) Thu, 07 Jan 2010 13:04:12 -0000
Re: Welcome to MRK - My Coral Farm: WELCOME!!! Great concept and some nice looking corals. Will be checking it out... http://bit.ly/6vDBiK
The yearly seashell madness appears to have started at Brick House Fabrics. Embroidered seahorse and corals out the door!
Brick_House_Fab (Brick House Fabrics) Thu, 07 Jan 2010 12:14:02 -0000
The yearly seashell madness appears to have started at Brick House Fabrics. Embroidered seahorse and corals out the door!
Tropical Salt Water Fish Only Tanks: 400 gallon aquarium, salt water corals, salt water tropical we also offer .. http://bit.ly/7VTvxi
SunnyFishTank (tkquincy) Thu, 07 Jan 2010 08:33:20 -0000
Tropical Salt Water Fish Only Tanks: 400 gallon aquarium, salt water corals, salt water tropical we also offer .. http://bit.ly/7VTvxi
says @kittpogi okay po ba sa Bataan White Corals? http://plurk.com/p/39u3uk
franciak (Kyle Francia) Thu, 07 Jan 2010 06:06:39 -0000
says @kittpogi okay po ba sa Bataan White Corals? http://plurk.com/p/39u3uk

Subscribe to Corals RSS feed