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Skeletal eroding band (SEB) is a disease of corals that appears a black or dark gray band that slowly advances over corals, leaving a spotted region of dead coral in its wake. It is the most common disease of corals in the Indian and Pacific Oceans, and is also found in the Red Sea. So far one agent has been clearly identified, the sessile heterotrich (ciliate) protozoan ''Halofolliculina corallasia''. This makes SEB the first coral disease known to be caused by a protozoan or any eukaryote. When ''H. corallasia'' divides, the daughter cells move to the leading edge of the dark band and produce a protective shell called a lorica. To do this, they drill into the coral's limestone skeleton, killing coral polyps in the process. A disease with very similar symptoms has been found in the Caribbean Sea, but has been given a different name as it is caused by a different species in the genus ''Halofolliculina'' and occurs in a different type of environment. ==Symptoms and history== Skeletal eroding band is visible as a black or dark gray band that slowly advances over corals, leaving a spotted region of dead coral in its wake.〔 〕 The spotted area distinguishes skeletal eroding band from black band disease,〔 which also forms an advancing black band but leaves a completely white dead area behind it. Skeletal eroding band was first noticed in 1988 near Papua New Guinea and then near Lizard Island in Australia's Great Barrier Reef, but was regarded as a gray variant of black band disease, as were instances off Mauritius in 1990. Surveys in 1994 in and around the Red Sea first identified the condition as a unique disease.〔 It is now considered the commonest disease of corals in the Indian and Pacific Oceans, especially in warmer or more polluted waters.〔 The spread of the disease across an infected coral has been measured at in the Red Sea and around the Great Barrier Reef. Corals of the families Acroporidae and Pocilloporidae are the most vulnerable to infection. A study in 2008 found that the infection spread at about per day in colonies of ''Acropora muricata'', eventually wiping out 95% of its victims. However, experiments showed that the disease easily spread to already dead and dying areas of corals but did not attack undamaged corals. 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「Skeletal eroding band」の詳細全文を読む スポンサード リンク
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