Description of a New Planktonic Mixotrophic Dinoflagellate Paragymnodinium shiwhaense n. gen., n. sp from the Coastal Waters off Western Korea: Morphology, Pigments, and Ribosomal DNA Gene Sequence

TY - JOUR

T1 - Description of a New Planktonic Mixotrophic Dinoflagellate Paragymnodinium shiwhaense n. gen., n. sp from the Coastal Waters off Western Korea: Morphology, Pigments, and Ribosomal DNA Gene Sequence

AU - Kang, Nam Seon

AU - Jeong, Hae Jin

AU - Moestrup, Øjvind

AU - Shin, Woongghi

AU - Nam, Seung Won

AU - Park, Jae Yeon

AU - Salas, Miguel F. de

AU - Kim, Ki Woo

AU - Noh, J.H.

PY - 2010/3

Y1 - 2010/3

N2 - The mixotrophic dinoflagellate Paragymnodinium shiwhaense n. gen., n. sp. is described from living cells and from cells prepared by light, scanning electron, and transmission electron microscopy. In addition, sequences of the small subunit (SSU) and large subunit (LSU) rDNA and photosynthetic pigments are reported. The episome is conical, while the hyposome is hemispherical. Cells are covered with polygonal amphiesmal vesicles arranged in 16 rows and containing a very thin plate-like component. There is neither an apical groove nor apical line of narrow plates. Instead, there is a sulcal extension-like furrow. The cingulum is as wide as 0.2-0.3 × cell length and displaced by 0.2-0.3 × cell length. Cell length and width of live cells fed Amphidinium carterae were 8.4-19.3 and 6.1-16.0 μm, respectively. Paragymnodinium shiwhaense does not have a nuclear envelope chamber nor a nuclear fibrous connective (NFC). Cells contain chloroplasts, nematocysts, trichocysts, and peduncle, though eyespots, pyrenoids, and pusules are absent. The main accessory pigment is peridinin. The sequence of the SSU rDNA of this dinoflagellate (GenBank AM408889) is 4% different from that of Gymnodinium aureolum, Lepidodinium viride, and Gymnodinium catenatum, the three closest species, while the LSU rDNA was 17-18% different from that of G. catenatum, Lepidodinium chlorophorum, and Gymnodinium nolleri. The phylogenetic trees show that this dinoflagellate belongs within the Gymnodinium sensu stricto clade. However, in contrast to Gymnodinium spp., cells lack nuclear envelope chambers, NFC, and an apical groove. Unlike Polykrikos spp., which have a taeniocyst-nematocyst complex, P. shiwhaense has nematocysts without taeniocysts. In addition, P. shiwhaense does not have ocelloids in contrast to Warnowia spp. and Nematodinium spp. Therefore, based on morphological and molecular analyses, we suggest that this taxon is a new species, also within a new genus.

AB - The mixotrophic dinoflagellate Paragymnodinium shiwhaense n. gen., n. sp. is described from living cells and from cells prepared by light, scanning electron, and transmission electron microscopy. In addition, sequences of the small subunit (SSU) and large subunit (LSU) rDNA and photosynthetic pigments are reported. The episome is conical, while the hyposome is hemispherical. Cells are covered with polygonal amphiesmal vesicles arranged in 16 rows and containing a very thin plate-like component. There is neither an apical groove nor apical line of narrow plates. Instead, there is a sulcal extension-like furrow. The cingulum is as wide as 0.2-0.3 × cell length and displaced by 0.2-0.3 × cell length. Cell length and width of live cells fed Amphidinium carterae were 8.4-19.3 and 6.1-16.0 μm, respectively. Paragymnodinium shiwhaense does not have a nuclear envelope chamber nor a nuclear fibrous connective (NFC). Cells contain chloroplasts, nematocysts, trichocysts, and peduncle, though eyespots, pyrenoids, and pusules are absent. The main accessory pigment is peridinin. The sequence of the SSU rDNA of this dinoflagellate (GenBank AM408889) is 4% different from that of Gymnodinium aureolum, Lepidodinium viride, and Gymnodinium catenatum, the three closest species, while the LSU rDNA was 17-18% different from that of G. catenatum, Lepidodinium chlorophorum, and Gymnodinium nolleri. The phylogenetic trees show that this dinoflagellate belongs within the Gymnodinium sensu stricto clade. However, in contrast to Gymnodinium spp., cells lack nuclear envelope chambers, NFC, and an apical groove. Unlike Polykrikos spp., which have a taeniocyst-nematocyst complex, P. shiwhaense has nematocysts without taeniocysts. In addition, P. shiwhaense does not have ocelloids in contrast to Warnowia spp. and Nematodinium spp. Therefore, based on morphological and molecular analyses, we suggest that this taxon is a new species, also within a new genus.

KW - Dinoflagellate taxonomy

KW - LSU

KW - nematocyst

KW - peduncle

KW - SSU

KW - SP-NOV GYMNODINIALES

KW - ELECTRON-MICROSCOPIC OBSERVATIONS

KW - LSU RDNA SEQUENCES

KW - FLAGELLAR APPARATUS

KW - LAKE TOVEL

KW - COMB.NOV

KW - AMPHIDINIUM DINOPHYCEAE

KW - PHYLOGENETIC ANALYSES

KW - GREEN DINOFLAGELLATE

KW - FEEDING-BEHAVIOR

U2 - 10.1111/j.1550-7408.2009.00462.x

DO - 10.1111/j.1550-7408.2009.00462.x

M3 - Journal article

C2 - 20487128

SN - 1066-5234

VL - 57

SP - 121

EP - 144

JO - Journal of Eukaryotic Microbiology

JF - Journal of Eukaryotic Microbiology

IS - 2

ER -