Periodicity of spore discharge in tropical Florideophyceae (Rhodophyta)

Data on the periodicity of carpospore and tetraspore discharge in 48 tropical benthic algal taxa from 25 genera are given. The time of maximum spore output in the laboratory occurred when populations on the shore would be submerged in sea water. Depending on the taxon, maximum spore output took place in the early morning, in the afternoon, or late in the evening. In taxa with small-sized spores, spore discharge took place during either the morning or the evening, or in a few cases during both periods, and high spore output generally occurred during the lower of the two high waters which occur daily in the Townsville region. In taxa with large-sized spores, and which generally inhabit the lower intertidal levels, spore liberation took place only in the afternoon, and high spore output then occurred during either the lower or the higher of the two high waters.