S. Itakura et al., CYST FORMATION IN THE RED TIDE FLAGELLATE HETEROSIGMA-AKASHIWO (RAPHIDOPHYCEAE), Journal of plankton research, 18(10), 1996, pp. 1975-1979
A natural population of Heterosigma akashiwo was collected and incubat
ed in the dark with autoclaved marine sediment. A portion of the cells
in the population changed into cysts, which were identical to H. akas
hiwo cysts found in the field. The cysts required at least 2 weeks of
mandatory dormancy before germination.