Morphology, molecular phylogeny, and pigment characterization of an isolate of the dinoflagellate <i>Pelagodinium bei</i> from Korean waters

doi:2015.30.3.183

Algae > Volume 30(3); 2015 > Article

Algae 2015;30(3): 183-195. doi: https://doi.org/10.4490/algae.2015.30.3.183

Morphology, molecular phylogeny, and pigment characterization of an isolate of the dinoflagellate Pelagodinium bei from Korean waters

Éric Potvin¹^,*, Hae Jin Jeong², Nam Seon Kang², Jae Hoon Noh³ and Eun Jin Yang¹

¹Division of Polar Ocean Environment, Korea Polar Research Institute, Incheon 406-840, Korea
²School of Earth and Environmental Sciences, College of Natural Sciences, Seoul National University, Seoul 151-747, Korea
³Marine Resources Research Department, KIOST, Ansan 425-600, Korea

*Corresponding Author

Email: ericpotvin@kopri.re.kr

ABSTRACT

The dinoflagellate genus Pelagodinium is genetically classified in distinct sub-clades and subgroups. However, it is difficult to determine whether this genetic diversity represents intra- or interspecific divergence within the genus since only the morphology of the type strain of the genus Pelagodinium, Pelagodinium bei, is available. An isolate associated with the genus Pelagodinium from Shiwha Bay, Korea, was recently cultured. This isolate was clustered with 3 to 4 strains from the Atlantic Ocean, Mediterranean Sea, and Indian Ocean. This cluster was distinct from the subgroup more closely associated with P. bei. The morphology of the isolate was analyzed using optical and scanning electron microscopy and was almost identical to that of P. bei except that this isolate had two series of amphiesmal vesicles (AVs) in the cingulum, unlike P. bei that has one series. When the pigment compositions of the isolate and P. bei were analyzed using highperformance liquid chromatography, these two strains had peridinin as a major accessory pigment and their pigment compositions were almost identical. In addition, the swimming behaviors of these two strains were very similar. The reexamination of the type culture of P. bei revealed two series in the cingulum as for the isolate. The new findings on the number of series of AVs in the cingulum, the pigment composition, and the swimming behaviors suggest that P. bei and the isolate are conspecific despite their genetic divergence. This study provides a basis to further understand the molecular classification within Pelagodinium combining genetic, morphological, pigment, and behavioral data.

Key words: foraminifera; Gymnodinium bei; pelagic symbiont; Suessiaceae; Suessiales