Recent discoveries of isolated water have lead to investigations of new organisms (see http://www.nature.com/news/russian-scientist-defends-lake-vostok-life-cla

Recent discoveries of isolated water have lead to investigations of new organisms (see http://www.nature.com/news/russian-scientist-defends-lake-vostok-life-claims-1.12578 http://www.nature.com/news/russian-scientist-defends-lake-vo...). This appears to be much older, but perhaps not as well isolated as Lake Vostok since there appears to be a connection with increased groundwater salinity in the area.