• Ocean Science Journal
• /
• 제41권2호
• /
• pp.75-95
• /
• 2006

The diversity of heterotrophic flagellates was examined at marine sediments around Cape Tribulation, Australia. The species described belong to the Alveolates, Apusomonadiae, Cercomonadida, Choanoflagellida, Cryptomonadida, Diplomonadida, Euglenozoa incertae sedis, Kathablepharidae, Kinetoplastida, Pedinellids, Stephanopogonidae, Stramenopiles, Stramenopiles incertae sedis, Thaumatomonadidae and Protista incertae sedis. Among the 51 species from 38 genera encountered in this study is one new taxon: Glissandra similis n. sp., and two new names are introduced: Goniomonas abrupta (Skvortzov 1924) nomen nodum and Cercomonas skvortzovi (Skvortzov 1977) nomen nodum. There was little evidence for endemism because most flagellates including one new taxon described here have been reported.

• Animal cells and systems
• /
• 제6권2호
• /
• pp.125-143
• /
• 2002

Heterotrophic flagellates occurring in the marine sediments of Inchon and Ganghwa Island are reported. Fifty-six species from 38 genera were encountered in this survey and two new taxa were recorded: Cyranomonas australis sp. nov. and Gweamonas unicus sp. nov. There was little evidence for endemism because all flagellates including the two new taxa described here have been found from other habitats in Australia which are geographically remote from Korea. This study supports the model that free-living heterotrophic flagellates have a world-wide distribution.

• 환경생물
• /
• 제33권2호
• /
• pp.148-152
• /
• 2015

Three marine heterotrophic flagellates from intertidal sediments of Gwang-Am beach and Garorim Bay, Korea were identified as Neometanema parovale Lee and Patterson 2014, Stephanopogon pattersoni Lee et al. 2014 and Thaumatomastix sp. These species are reported taxonomically for the first time from Korea, and are described with illustrations and micrographs. Diagnostics of these species are as follows. Neometanema parovale (Euglenozoa): size in vivo, $10{\sim}23{\mu}m\;long$ with 22 pellicular strips, ingestion apparatus barely visible by light microscopy and two flagella pointed in different directions when moving. Stephanopogon pattersoni (Percolozoa): size in vivo, $20{\sim}33{\mu}m\;long$, with 6 ventral and 1 ventro-lateral ciliary rows, and three barbs. Thaumatomastix sp. (Cercozoa): size in vivo, $14{\sim}17{\mu}m$ with body scales and spines, and two flagella with one naked and one scaled.

• ALGAE
• /
• 제22권1호
• /
• pp.23-29
• /
• 2007

Free-living heterotrophic stramenopile flagellates, which lack chloroplasts, were encountered in deep-sea sediments of Gippsland Basin (Australia) and classified into 10 species (8 genera, 5 families, 3 orders). Their descriptions were based on living specimens by light microscopy. Those species rarely found in this study were Bicosoeca gracilipes, Caecitellus parvulus, Cafeteria minuta, Cafeteria roenbergensis, Pseudobodo tremulans, Spumella sp., Paraphysomonas sp., Actinomonas mirabilis, Ciliophrys infusionum and Developayella elegans. Their morphological characters and geographic distribution are presented.

• Journal of Species Research
• /
• 제9권4호
• /
• pp.448-454
• /
• 2020

Nine free-living heterotrophic flagellates were cultured from marine intertidal sediments and freshwater sediments from Korea. These species are described with uninterpreted records based on light microscopy of living cells and reported taxonomically for the first time from Korea. Diagnostics of these species are as follows; Notosolenus hemicircularis: 9-11.8 ㎛ long with flagellar reservoir, ventrally flattened and dorsally convex with hyaline semicircular collar around short anterior neck, and 8 ridges on cell surface. Thecamonas tranhens: 4.5-7.1 ㎛ long, plastic with proboscis comprising an anterior flagellum surrounded by membranous sleeve. Bodomorpha minima: 4.5-7.0 ㎛ long, rigid with small rostrum in anterior end and active anterior flagellum. Cercomonas hiberna: 5.6-10.9 ㎛ long, very plastic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Cercomonas pellucida: 7.5-13 ㎛ long, plastic with pseudopodia, cytoplasmic strand and single contractile vacuole. With nucleus closely connected to basal bodies. Eocercomonas echina: 4.7-6.5 ㎛ long, plastic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Paracercomonas astra: 5.7-7.3 ㎛ long, moderately metabolic with pseudopodia, cytoplasmic strand and 1 or 2 contractile vacuoles. Paracercomonas minima: 5-9 ㎛ long, metabolic with pseudopodia, cytoplasmic strand and single contractile vacuole. Paracercomonas producta: 6.1-9.9 ㎛ long, very metabolic with pseudopodia, long cytoplasmic strand and single contractile vacuole.

• 한국해양학회지:바다
• /
• 제10권1호
• /
• pp.19-30
• /
• 2005

강화도 장화리의 펄 갯벌에 서식하는 저서 원생동물 군집의 계절 분포 및 섭식률을 파악하기 위하여 2002년 4월부터 2004년 4월까지 총 3개의 정점을 선정하여 2-3개월 간격으로 조사를 수행하였다. 저서 원생동물의 현존량과 생물량은 섬모충류와 종속영양 편모류에 의해 98% 이상 우점하여 나타났으며, 그 외 종속영양 와편모류와 아메바 그룹이 일부 시기에 관찰되었으나 중요하지 않은 그룹으로 나타났다. 종속영양 편모류의 현존량과 탄소량은 각각 $0.2-5.9{\times}10^5\;cells\;cm^{-3}$와 $0.02-9.2\;{\mu}C\;cm^{-3}$로 분포하였으며, 생물량은 춘계와 추계에 비교적 높은 분포를 보였다. 종속영양 편모류는 표충 2.5 mm 이내에서 다른 층에 비해 높은 분포를 보였으며, 종속영양 편모류의 수평적 분포는 정점별로 차이가 없는 것으로 나타났다. 종속영양 편모류는 $10{\mu}m$이하의 크기에 의하여 주로 우점하여 나타났으나, 2월과 4월 사이에 $20{\mu}m$ 이상의 종속영양 유글레나가 높게 출현하였다 섬모충류의 현존량과 생물량은 각각 $0.1-17.8{\times}10^3\;cells\;cm^{-3}$와 $0.02-9.1\;{\mu}gC\;cm^{-3}$ 범위로 분포하였으며 춘계와 추계에 높은 분포를 보였다. 섬모충류 그룹은 주로 하모류에 의해 우점 하였으며, 계절별로 두드러진 우점 종들은 관찰되지 않았다. 섬모충류의 수직적 분포는 표층 2.5 mm이내에서 높은 분포를 보였으며, 정점별 분포는 조간대 상부 정점에 비해 조간대 하부 정점에서 높은 분포를 보였다. 섬모충류의 시.공간적 분포는 저서 미세조류의 생물량 분포와 유사한 양상을 보였다. 조사기간동안 저서 원생동물 그룹의 탄소량은 섬모충류에 의해 평균 66%의 높은 우점률을 보였으며, 저서 원생동물의 계절변동은 저서 미세조류의 변동과 유사한 양상을 보였다. 본 연구에서 저서 원생동물의 섭식률을 측정한 결과 박테리아 생산력과 저서 미세조류 생산력의 각각 13.4-40.7%와 20.1-36.4%를 제거하였으며, 박테리아에 대한 섭식률은 섬모충류에 비해 종속영양 편모류에 의해 더 높은 것으로 나타났다. 박테리아와 돌말류에 대한 저서 원생동물의 섭식률은 춘계에 가장 높았으며 저서 미세생물 먹이 망에서 저서 원생동물은 미세생물 군집의 생물량이 높은 춘계에 박테리아와 돌말류의 포식자로서 중요한 역할을 하고 있음을 시사하였다.

• 한국해양학회지
• /
• 제28권1호
• /
• pp.69-71
• /
• 1993

지금 까지 자연상태에서 해산지각류의 먹이로서는 주로 중심목 규조류가 섭식되고 있는 것으로 알려져 왔다. 그러나 그들의 장내용물질들은 재검사한 결과, 이들 규조류 외에 편모조유들 역시 해산지각류의 먹이로서 중요한 것으로 판단되었다. 따라서 Prorocentrum micans, Protoperidinium sp.등과 미동정된 편모조류 등도 해산지각류의 중요한 먹이로서 추가되어야 할 것으로 밝혀졌다.

• Journal of Microbiology
• /
• 제33권3호
• /
• pp.222-227
• /
• 1995

We have examined DNase I sensitivity of .betha.-tubulin and flagellar calmodulin genes which are transiently and coordinately activated differentiation of Naegleria gruberi amebae into flagellates. The DNase I sensitivity of .betha.-tubulin and flagellar calmodulin genes changed in parallel with the changes in transcriptional activity of the respective genes during differentiation. The two genes were resistant to DNase I inamebae stage when transcription of the two genes was inactive. Forthy minutes after initiation of differentiation, when the two genes were most actively being transcribed, the two genes showed the highest sensitsivity to DNase I. One hundred and twenty minutes after initiation, the differentiation was completed and transcriptional activity of the two genes decreased to a low level. At this stage, the two genes were resistant to DNase I treatment like the ones at the amebae stage. This change in the DNase I sensitivity of the two genes was not observed when transcription of the two genes was blocked by adding cycloheximide at the beginning of differentiation.

• 한국환경과학회지
• /
• 제16권7호
• /
• pp.855-863
• /
• 2007

In order to understand the temporal distribution of pico- and nanoplankton and factors controlling its distribution at a station in Okkye Bay of Masan Bay located in the southern part of Korea, this study was conducted on two weeks interval from April 2005 to April 2006, and several abiotic and biotic factors were measured. During the study, picoplankton consisted of picoflagellates, cyanobacteria and heterotrophic bacteria, and nanoplankton consisted of nanoflagellates excluding dinoflagellates. The concentration of chlorophyll-a (chl-a) was a mean of $4.33\;{\mu}g/L$, and the nanoplanktonic ($<20\;{\mu}m$) chl-a size fraction was a mean of 39.5 % and significantly correlated with water temperature. The abundances of cyanobacteria and photosynthetic flagellates (PF) were means of $24.4{\times}10^{3}\;cells/mL\;and\;2.87{\times}10^{3}\;cells/mL$, respectively. The contribution of picoflagellates to the PF abundance varied among the sampling occasions and was a mean of 29 %, but to the PF carbon biomass was 2.6 % only. The PF abundance had significant relationships with water temperature, and silicate and TIN concentrations, suggesting that the PF abundance seemed to be primarily bottom-up regulated. The abundance of heterotrophic bacteria was a mean of $3.18{\times}10^{6}\;cells/mL$ and unlike other ecosystems it did not have relationships with chl-a and heterotrophic flagellates (HF), suggesting that bacterial abundance did not seem to be bottom-up or top-down regulated. HF mostly consisted of cells less than $5{\mu}m$ and its abundance was a mean of $2.71{\times}10^{3}\;cells/mL$. Of the HF abundance, picoflagellates occupied about 31 %, and occupied about 9 % of the HF carbon biomass. HF grazing activity on heterotrophic bacteria was relatively low and removed about 10 % of bacterial abundance, suggesting that HF might not be major consumers of bacteria and there seems to be other consumers in Okkye Bay. These results suggest that Okkye Bay may have a unique microbial ecosystem.

• Journal of the korean society of oceanography
• /
• 제37권2호
• /
• pp.58-65
• /
• 2002

The study of microbial communities in sediments is impaired by the lack of reliable extraction methods. This study reports on the efficiency of recovery of a method for extracting bacteria, protists and diatoms from sandy sediments using a modified decant/fix method. The best extractions were achieved after fixation with a microtubule stabilising fixative and subsequent sonication for 80 seconds. We estimate that the efficiencies of recovery of bacteria and mixed heterotrophic flagellates were $96.4{\pm}3.5\%$ and $96.9{\pm}4.6\%$, respectively. Diatoms were recovered with an efficiency of 38-83% and varied considerably from species to species. This study suggests that the decant/fix method is effective in extracting small cells such as bacteria and heterotrophic flagellates, and that the efficiency of recovery of the method varies due to cell length and different types of organisms. When microbial carbon biomass had been underestimated by up to 32%, with much of that relating to larger cells such as microalgae and ciliates. We note that the corrected abundances may be still a subset of the total numbers present.