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''Lophelia pertusa'', the only species in the genus ''Lophelia'', is a cold-water coral which grows in the deep waters throughout the North Atlantic ocean, as well as parts of the Caribbean Sea and Alboran Sea.〔C. Michael Hogan. 2011. (''Alboran Sea''. eds. P. Saundry & C. J. Cleveland. Encyclopedia of Earth. National Council for Science and the Environment. Washington DC )〕 ''L. pertusa'' reefs are home to a diverse community, however the species is extremely slow growing and may be harmed by destructive fishing practices, or oil exploration and extraction. ==Biology== ''Lophelia pertusa'' is a reef building, deep water coral, which is unusual for its lack of zooxanthellae - the symbiotic algae which lives inside most tropical reef building corals. ''Lophelia'' lives between and over depth, but most commonly at depths of , where there is no sunlight, and a temperature range from about . As a coral, it represents a colonial organism, which consists of many individuals. New polyps live and build upon the calcium carbonate skeletal remains of previous generations. Living coral ranges in colour from white to orange-red. Unlike most tropical corals, the polyps are not interconnected by living tissue. Radiocarbon dating indicates that some ''Lophelia'' reefs in the waters off North Carolina may be 40,000 years old, with individual living coral bushes as much as 1,000 years old. The coral reproduces by budding off new polyps and by producing free-living planktonic larvae which float in the water until they find a suitable surface to attach to and grow on. ''Lophelia'' reefs can grow to high. The largest recorded ''Lophelia'' reef, Røst Reef, measures and lies at a depth of off the Lofoten Islands, Norway.〔Coral reefs in Norway (2002). ''(Large Lophelia pertusa reef discovered off Røst in Lofoten. )'' Institute of Marine Research, Norway.〕 When this is seen in terms of a growth rate of around 1 mm per year, the great age of these reefs becomes apparent. Polyps at the end of branches feed by extending their tentacles and straining plankton from the seawater. The spring bloom of phytoplankton and subsequent zooplankton blooms, provide the main source of nutrient input to the deep sea. This rain of dead plankton is visible on photographs of the seabed and stimulates a seasonal cycle of growth and reproduction in ''Lophelia''. This cycle is recorded in patterns of growth, and can be studied to investigate climatic variation in the recent past. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lophelia」の詳細全文を読む スポンサード リンク
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