Morphology and rbcL sequences of Caulacanthus okamurae Yamada (Gigartinales, Rhodophyta) from Korea

Algae > Volume 16(1); 2001 > Article

Algae 2001;16(1): 25-34.

Hae-Bok Lee, Jae Wan Lee, Han-Gu Choi, Wook Jae Lee, Jong-In Kim

Department of Biology, Chongju University, BK21, School of Biological Sciences, Seoul National University, Korea Research Institute of Bioscience & Technology

ABSTRACT

The red alga, Caulacanthus okamurae Yamada, which Yoshida et al. (1995, 2000) recently proposed to be synonymized with C. ustulatus (Turner) Kutzing described in southern Spain, was collected in the upper intertidal zone along the coast of Korea. We investigated morphology and rbcL sequences of the plants to assess the taxonomic criteria of the species. This species is very similar to C. ustulatus in plant height, branching pattern, shape of axial cell, number of pericentral cells, and reproductive structure. The former, however, is different from the latter in thickness of branches. There is no nucleotide difference of rbcL sequences among three isolations of C. okamurae from Korea, but there are 8 and 115 bp differences between Korean isolations and two of C. ustulatus from Brittany, France and Swakopmund, Namibia. Our morphological and rbcL sequence data suggested that the populations of C. okamurae from Korea and C. ustulatus from Brittany, France could be different ones of the same species. Therefore, we postpone taxonomic judgement for C. okamurae from Korea, China and Japan until such a time as molecular data of C. ustulatus from the type locality are available and the origin of the Brittany isolation is elucidated.

Key words: Caulacanthus okamurae, C. ustulatus, Gigartinales, morphology, rbcL sequences, Rhodophyta, taxonomy