This video is called Alcyonium digitatum.
Monday 06 August 2012
The Netherlands’ only variety of coral, dead man’s thumb, has reappeared in the Oosterschelde in Zeeland, having appeared to have died out in 2011.
Alcyonium digitatum likes strongly flowing, cold sea water and seemed to have died out in 2010 and early 2011. Scientists said this could be because of the warming of the seas.
However, since mid-2011 the coral has made a come-back and divers report seeing a increasing number of them, say press reports.
The dead man’s thumb is so called because it is white and shaped like a thumb.
See also here.