Algae. 1998; 13(2): 199-206.

Life History and Taxonomyof Aglaothamnion oosumiense Itono(Ceramiaceae, Rhodophyta)

Ok-Kyong Chah, Gwang-Hoon Kim

Department of Biology, Kongju National University

Life history and post-fertilization process of Aglaothamnion oosumiense from Korea were studied in culture. This species showed a Polysiphonia-type life history with dioecious gametophyte as well as asexual reproduction via parasporangium on male plants. The occurrence of parasporangiate plants was not affected by environment factors nor inherited strictly to the next generation. Most (>95%) of the paraspores developed into male plants, while less than 5% of paraspores became parasporangiate male plants were also observed. Each carpogonial branch had two auxiliary cells, which divided distally to produce the primary gonimoblast initials, respectively, before the foot cells were cut off proximately from it by intercalary divisions. Two carposporophytes resulted from a successful fertilization. Morphologically, Aglaothamnion oosumiense resembled Aglaothamnion callophyllidicola (Yamada) Boo, Lee, Rueness et Yoshida, and the taxonomic characters separating them were found to be unstable. The taxonomic relationship between the two species, therefore, should be critically reassessed with a thorough reexamination including their type specimens.

Keywords : Aglaothamnion oosumiense, Ceramiaceae, life history, post-fertilization, Rhodophyta