On the ecology of Acoela living in the Arctic Sea ice

A common meiofauna representative found in the pore system of the arctic sea ice from the Laptev, Barents and Greenland Seas was found to be a species of the Acoela characterized, among other features, by its bright red colour. It was studied by video recording of specimens moving in slices of ice and in 0 degreesC sea water cultures after thawing of the ice. It is evidently well adapted to live and move in the partly very narrow brine channels. It has a great vertical distribution in the ice, but has its highest concentration in the lowermost 15 cm. In ice core samples from the Greenland Sea densities of up to 16,200 specimens per square meter were found. Diatoms were seen being eaten and were also found in the digestive parenchyma of sectioned specimens. Once a young nematode was observed being eaten. A description of the acoel species is given elsewhere.