Systematic Relationship of Unicellular Red Algae: from the Phenetics to the Phylogeny

Algae > Volume 15(1); 2000 > Article

Algae 2000;15(1): 7-11.

Yoshiaki Hara, Akiko Yokoyama, Ji-Hee Kim

ABSTRACT

The systematic relationship of the unicellular red algae based on their morphological, physiological and habitual characteristics was discussed by referring to the results of their molecular photogenetic analyses, using 18 rRNA and psbA genes. Five groups (named as one ancestral stock; Porphyridium Group (-G) and other four groups; Rhodospora-, Rhodella-, Rodosorus- and Cyanidium-G) previously reported were partially supported by the molecular phylogeny which showed four phylogenetic groups. However, two of them made a clade with multicellular ones. In particular, Porphyridium-G was recognized as an ancestral stock rather than an evolutionary lineage. Consequently, the basic framework of the systematic relationship of uncellular reds has to be reconstructed, after taking new findings of molecular information into consideration. The correspondence with the phenetics and photogenetic relationships of unicellular reds is the center of the present Mini-review.

Key words: Cyanidium, 18S rRNA, molecular phylogeny, Porhiridium, Rhodella, Rhodosorus, systematic relationship, ultrastrucuture, unicellular red algae