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Articles Corrected proof have been peer-reviewed and accepted, which are not yet assigned to volumes/issues, but are citable by Digital Object Identifier (DOI).
Hepatic cecum: a key integrator of immunity in amphioxus
Baozhen Qu, Shicui Zhang, Zengyu Ma, Zhan Gao
, Available online  , doi: 10.1007/s42995-020-00080-w
Abstract(3) HTML PDF Springerlink
The vertebrate liver is regarded as an organ essential to the regulation of immunity and inflammation as well as being central to the metabolism of nutrients. Here, we discuss the functions that the hepatic cecum of amphioxus plays in the regulation of immunity and inflammation, and the molecular basis of this. It is apparent that the hepatic cecum performs important roles in the immunity of amphioxus including immune surveillance, clearance of pathogens and acute phase response. Therefore, the hepatic cecum, like the vertebrate liver, is an organ functioning as a key integrator of immunity in amphioxus.
Marine-derived fungi as a source of bioactive indole alkaloids with diversifed structures
Zhi-Hui Meng, Tian-Tian Sun, Guo-Zheng Zhao, Yu-Fei Yue, Qing-Hua Chang, Hua-Jie Zhu, Fei Cao
, Available online  , doi: 10.1007/s42995-020-00072-w
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Marine-derived fungi are well known as rich sources of bioactive natural products. Growing evidences indicated that indole alkaloids, isolated from a variety of marine-derived fungi, have attracted considerable attention for their diverse, challenging structural complexity and promising bioactivities, and therefore, indole alkaloids have potential to be pharmaceutical lead compounds. Systemic compilation of the relevant literature. In this review, we demonstrated a comprehensive overview of 431 new indole alkaloids from 21 genera of marine-derived fungi with an emphasis on their structures and bioactivities, covering literatures published during 1982-2019.
Cultivation and diversity analysis of novel marine thraustochytrids
Lu Lyu, Qiuzhen Wang, Guangyi Wang
, Available online  , doi: 10.1007/s42995-020-00069-5
Abstract(26) HTML PDF Springerlink
Thraustochytrids are a group of unicellular marine heterotrophic protists, and have long been known for their biotechnological potentials in producing squalene, polyunsaturated fatty acids (PUFAs) and other bioactive products. There are less than a hundred known strains from diverse marine habitats. Therefore, the discovery of new strains from natural environments is still one of the major limitations for fully exploring this interesting group of marine protists. At present, numerous attempts have been made to study thraustochytrids, mainly focusing on isolating new strains, analyzing the diversity in specific marine habitats, and increasing the yield of bioactive substances. There is a lack of a systematic study of the culturable diversity, and cultivation strategies. This paper reviews the distribution and diversity of culturable thraustochytrids from a range of marine environments, and describes in detail the most commonly used isolation methods and the control of culture parameters. Furthermore, the perspective approaches of isolation and cultivation for the discovery of new strains are discussed. Finally, the future directions of novel marine thraustochytrid research are proposed. The ultimate goal is to promote the awareness of biotechnological potentials of culturable thraustochytrid strains in industrial and biomedical applications.
Application of in situ cultivation in marine microbial resource mining
Dawoon Jung, Liwei Liu, Shan He
, Available online  , doi: 10.1007/s42995-020-00063-x
Abstract(84) HTML PDF Springerlink
Microbial communities in marine habitats are regarded as underexplored reservoirs for discovering new natural products with potential application. However,only a few microbes in nature can be cultivated in the laboratory. This has led to the development of a variety of isolation and cultivation methods,and in situ cultivation is one of the most popular. Diverse in situ cultivation methods,with the same basic principle,have been applied to a variety of environmental samples. Compared with conventional approaches,these new methods are able to cultivate previously uncultured and phylogenetically novel microbes,many with biotechnological potential. This review introduces the various in situ cultivation methods for the isolation of previously uncultured microbial species and their potential for marine microbial resource mining. Furthermore,studies that investigated the key and previously unidentifed mechanisms of growing uncultivated microorganisms by in situ cultivation,which will shed light on the understanding of microbial uncultivability,were also reviewed.
From ecophysiology to cultivation methodology: filling the knowledge gap between uncultured and cultured microbes
Nimaichand Salam, Wen-Dong Xian, Mipeshwaree Devi Asem, Min Xiao, Wen-Jun Li
, Available online  , doi: 10.1007/s42995-020-00064-w
Abstract(126) HTML PDF Springerlink
Earth is dominated by a myriad of microbial communities, but the majority fails to grow under in situ laboratory conditions. The basic cause of unculturability is that bacteria dominantly occur as biofilms in natural environments. Earlier improvements in the culture techniques are mostly done by optimizing media components. However, with technological advancement particularly in the field of genome sequencing and cell imagining techniques, new tools have become available to understand the ecophysiology of microbial communities. Hence, it becomes easier to mimic environmental conditions in the culture plate. Other methods include co-culturing, emendation of growth factors, and cultivation after physical cell sorting. Most recently, techniques have been proposed for bacterial cultivation by employing genomic data to understand either microbial interactions (network-directed targeted bacterial isolation) or ecosystem engineering (reverse genomics). Hopefully, these techniques may be applied to almost all environmental samples, and help fill the gaps between the cultured and uncultured microbial communities.
Planktonic microbial eukaryotes in polar surface waters:recent advances in high-throughput sequencing
Qian Liu, Qiannan Zhao, Andrew McMinn, Eun Jin Yang, Yong Jiang
, Available online  , doi: 10.1007/s42995-020-00062-y
Abstract(166) HTML PDF Springerlink
Marine microbial eukaryotes are important primary producers and play critical roles in key biogeochemical cycles. Recent advances in sequencing technology have focused attention on the extent of microbial biodiversity, revealing a huge, previously underestimated phylogenetic diversity with many new lineages. This technology has now become the most important tool to understand the ecological significance of this huge and novel diversity in polar oceans. In particular, high-throughput sequencing technologies have been successfully applied to enumerate and compare marine microbial diversity in polar environments. Here, a brief overview of polar microbial eukaryote diversity, as revealed by in-situ surveys of the high-throughput sequencing on 18S rRNA gene, is presented. Using these 'omic' approaches, further attention still needs to be focused on differences between specific locations and/or entire polar oceans and on bipolar comparisons of diversity and distribution.
The parasitic dinoflagellate Hematodinium infects marine crustaceans
Caiwen Li, Meng Li, Qian Huang
, Available online  , doi: 10.1007/s42995-020-00061-z
Abstract(184) HTML PDF Springerlink
Hematodinium is a type of parasitic dinoflagellate that infects marine crustaceans globally. The parasite lives mainly in the hemolymph or hemocoels of affected hosts, and results in mortalities due to malfunction or loss of functions of major organs. In recent years, the parasite had developed into an emerging epidemic pathogen not only affecting wild populations of economically valuable marine crustaceans in western countries but also the sustainable yield of aquaculture of major crabs in China. The epidemics of the parasitic diseases expanded recently in the coastal waters of China, and caused frequent outbreaks in aquaculture of major crab species, especially Portunus trituberculatus and Scylla paramamosain. In addition, the pathogen infected two species of co-cultured shrimps and multiple cohabitating wild crabs, implying it is a significant threat to the sustainable culture of commercially valuable marine crustaceans. In particular, the polyculture system that is widely used along the coast of China may facilitate the spread and transmission of the pathogen. Thus, to provide a better understanding of the biological and ecological characteristics of the parasitic dinoflagellate and highlight important directions for future research, we have reviewed the current knowledge on the taxonomy, life cycle, pathogenesis, transmission and epidemiology of Hematodinium spp. Moreover, ecological countermeasures have been proposed for the prevention and control of the emerging infectious disease.
Strategies for culturing active/dormant marine microbes
Da-Shuai Mu, Yang Ouyang, Guan-Jun Chen, Zong-Jun Du
, Available online  , doi: 10.1007/s42995-020-00053-z
Abstract(135) HTML PDF Springerlink
Microorganisms are ubiquitous in the ocean environment and they play key roles in marine ecosystem function and service. However,many of their functions and phenotypes remain unknown because indigenous marine bacteria are mostly difficult to culture. Although many novel techniques have brought previously uncultured microbes into laboratory culture,there are still many most-wanted or key players that need to be cultured from marine environments. This review discusses possible reasons for 'unculturable microbes' and categorizes uncultured bacteria into three groups: dominant active bacteria,rare active bacteria,and dormant bacteria. This review also summarizes advances in cultivation techniques for culturing each group of unculturable bacteria. Simulating the natural environment is an effective strategy for isolating dominant active bacteria,whereas culturomics and enrichment culture methods are proposed for isolating rare active bacteria. For dormant bacteria,resuscitation culture is an appropriate strategy. Furthermore,the review provides a list of the most-wanted bacteria and proposes potential strategies for culturing these bacteria in marine environments. The review provides new insight into the development of strategies for the cultivation of specific groups of uncultured bacteria and therefore paves the way for the detection of novel microbes and their functions in marine ecosystems.
Viable but nonculturable bacteria and their resuscitation: implications for cultivating uncultured marine microorganisms
Xiao-Hua Zhang, Waqar Ahmad, Xiao-Yu Zhu, Jixiang Chen, Brian Austin
, Available online  , doi: 10.1007/s42995-020-00041-3
Abstract(249) HTML PDF Springerlink
Culturing has been the cornerstone of microbiology since Robert Koch first successfully cultured bacteria in the late nineteenth century. However, even today, the majority of microorganisms in the marine environment remain uncultivated. There are various explanations for the inability to culture bacteria in the laboratory, including lack of essential nutrients, osmotic support or incubation conditions, low growth rate, development of micro-colonies, and the presence of senescent or viable but nonculturable (VBNC) cells. In the marine environment, many bacteria have been associated with dormancy, as typified by the VBNC state. VBNC refers to a state where bacteria are metabolically active, but are no longer culturable on routine growth media. It is apparently a unique survival strategy that has been adopted by many microorganisms in response to harsh environmental conditions and the bacterial cells in the VBNC state may regain culturability under favorable conditions. The resuscitation of VBNC cells may well be an important way to cultivate the otherwise uncultured microorganisms in marine environments. Many resuscitation stimuli that promote the restoration of culturability have so far been identified; these include sodium pyruvate, quorum sensing autoinducers, resuscitation-promoting factors Rpfs and YeaZ, and catalase. In this review, we focus on the issues associated with bacterial culturability, the diversity of bacteria entering the VBNC state, mechanisms of induction into the VBNC state, resuscitation factors of VBNC cells and implications of VBNC resuscitation stimuli for cultivating these otherwise uncultured microorganisms. Bringing important microorganisms into culture is still important in the era of high-throughput sequencing as their ecological functions in the marine environment can often only be known through isolation and cultivation.
Diversity, metabolism and cultivation of archaea in mangrove ecosystems
Cui-Jing Zhang, Yu-Lian Chen, Yi-Hua Sun, Jie Pan, Ming-Wei Cai, Meng Li
, Available online  , doi: 10.1007/s42995-020-00081-9
Abstract(3) HTML PDF Springerlink
Mangroves comprise a globally significant intertidal ecosystem that contains a high diversity of microorganisms, including fungi, bacteria and archaea. Archaea is a major domain of life that plays important roles in biogeochemical cycles in these ecosystems. In this review, the potential roles of archaea in mangroves are briefly highlighted. Then, the diversity and metabolism of archaeal community of mangrove ecosystems across the world are summarized and Bathyarchaeota, Euryarchaeota, Thaumarchaeota, Woesearchaeota, and Lokiarchaeota are confirmed as the most abundant and ubiquitous archaeal groups. The metabolic potential of these archaeal groups indicates their important ecological function in carbon, nitrogen and sulfur cycling. Finally, some cultivation strategies that could be applied to uncultivated archaeal lineages from mangrove wetlands are suggested, including refinements to traditional cultivation methods based on genomic and transcriptomic information, and numerous innovative cultivation techniques such as single-cell isolation and high-throughput culturing (HTC). These cultivation strategies provide more opportunities to obtain previously uncultured archaea.
Co-culture: stimulate the metabolic potential and explore the molecular diversity of natural products from microorganisms
Xiao-Yue Peng, Jin-Tao Wu, Chang-Lun Shao, Zhi-Yong Li, Min Chen, Chang-Yun Wang
, Available online  , doi: 10.1007/s42995-020-00077-5
Abstract(4) HTML PDF Springerlink
Microbial secondary metabolites have long been considered as potential sources of lead compounds for medicinal use due to their rich chemical diversity and extensive biological activities. However, many biosynthetic gene clusters remain silent under traditional laboratory culture conditions, resulting in repeated isolation of a large number of known compounds. The co-culture strategy simulates the complex ecological environment of microbial life by using an ecology-driven method to activate silent gene clusters of microorganisms and tap their metabolic potential to obtain novel bioactive secondary metabolites. In this review, representative studies from 2017 to 2020 on the discovery of novel bioactive natural products from co-cultured microorganisms are summarized. A series of natural products with diverse and novel structures have been discovered successfully by co-culture strategies, including fungus-fungus, fungus-bacterium, and bacterium-bacterium co-culture approaches. These novel compounds exhibited various bioactivities including extensive antimicrobial activities and potential cytotoxic activities, especially when it came to disparate marine-derived species and cross-species of marine strains and terrestrial strains. It could be concluded that co-culture can be an effective strategy to tap the metabolic potential of microorganisms, particularly for marine-derived species, thus providing diverse molecules for the discovery of lead compounds and drug candidates.
Research Paper
High chromosomal evolutionary dynamics in sleeper gobies (Eleotridae) and notes on disruptive biological factors in Gobiiformes karyotypes (Osteichthyes, Teleostei)
Simião Alefe Soares da Silva, Paulo Augusto de Lima-Filho, Clóvis Coutinho da Motta-Neto, Gideão Wagner Werneck Félix da Costa, Marcelo de Bello Cioffi, Luiz Antônio Carlos Bertollo, Wagner Franco Molina
, Available online  , doi: 10.1007/s42995-020-00084-6
Abstract(4) HTML PDF Springerlink
The order Gobiiformes is made up of more than 2200 species, representing one of the most diverse groups among teleost fishes. The biological causes for the tachytelic karyotype evolution of the gobies have not yet been fully studied. Here we expanded cytogenetic data for the Eleotridae family, analyzing the neotropical species Dormitator maculatus, Eleotris pisonis, Erotelis smaragdus, and Guavina guavina. In addition, a meta-analytical approach was followed for elucidating the karyotype diversification versus biological aspects (habitat and egg type) of the Gobiiformes. The species E. smaragdus and E. pisonis present 2n = 46 acrocentric chromosomes (NF = 46), D. maculatus 2n = 46 (36sm + 4st + 6a; NF = 86), and G. guavina, the most divergent karyotype, with 2n = 52 acrocentric chromosomes (NF = 52). Besides numeric and structural diversification in the karyotypes, the mapping of rDNAs and microsatellites also showed noticeable numerical and positional variation, supporting the high chromosomal evolutionary dynamism of these species. In Gobiiformes, karyotype patterns which are more divergent from the basal karyotype (2n = 46a) are associated with characteristics less effective to dispersion, such as the benthic habit. These adaptive characteristics, connected with the organization of the repetitive DNA content in the chromosomes, likely play a synergistic role in the remarkable karyotype diversification of this group.
Characterization of Bacillus phage Gxv1, a novel lytic Salasvirus phage isolated from deep-sea seamount sediments
Xun Guo, Tianyou Zhang, Min Jin, Runying Zeng
, Available online  , doi: 10.1007/s42995-020-00074-8
Abstract(21) HTML PDF Springerlink
Seamounts are hotspots for marine life, but to date, no bacteriophages have been reported. Here, a novel Bacillus podophage (named as Bacillus phage Gxv1) was isolated from deep-sea seamount sediments of the western Pacific Ocean (~ 5790 m). Phage Gxv1 has a hexameric head ~ 42-53 nm in diameter and a short tail of ~ 30 nm long, which is a typical feature of the Podoviridae family. One-step curve analysis showed that Gxv1 is a lytic phage that can initiate host lysis within 3.5 h post-infection, and has a relatively large burst size. The 21, 781-bp genome contains 34 predicted genes, and the G?+?C content of phage Gxv1 is 39.69%. Whole-genome comparison of phage Gxv1 with known bacteriophages, using BlastN analysis against the IMG/VR database, revealed that phage Gxv1 is closely related to Bacillus phage phi29 that infects Bacillus subtilis, and their genome-wide similarity is 93.62%. Phylogenetic analysis based on DNA polymerase showed that phage Gxv1 belongs to the Salasvirus genus. Multiple genome alignment showed that phage Gxv1 shares a high level of sequence similarity and common gene order with Bacillus phage phi29. However, some sequences are unique to phage Gxv1, and this region contains genes encoding DNA packing protein, DNA replication protein, and unknown protein. These sequences exhibit low sequence similarity to known bacteriophages, highlighting an unknown origin of these sequences. This study will help improve our understanding of the Salasvirus genus and phage diversity in deep-sea seamounts.
Spatial distribution of planktonic ciliates in the western Pacific Ocean: along the transect from Shenzhen (China) to Pohnpei (Micronesia)
Hungchia Huang, Jinpeng Yang, Shixiang Huang, Bowei Gu, Ying Wang, Lei Wang, Nianzhi Jiao, Dapeng Xu
, Available online  , doi: 10.1007/s42995-020-00075-7
Abstract(24) HTML PDF Springerlink
Planktonic ciliates have been recognized as major consumers of nano- and picoplankton in pelagic ecosystems, playing pivotal roles in the transfer of matter and energy in the microbial loop. However, due to the difficulties in identification, the species composition of ciliate assemblages, especially for the small, fragile, and naked species that usually dominate the ciliate communities in the oceanic waters, remains largely unknown. In the present study, 22 stations along the transect from Shenzhen (China) to Pohnpei (Micronesia) were sampled for the enumeration of picoplankton and nanoflagellates. In addition, pigment analysis of major phytoplankton groups along with the measurements of environmental variables including temperature, salinity, and nutrients were also carried out. Ciliates were identified at species level using quantitative protargol stain to reveal the species composition and their distribution patterns from off-shore to open ocean. Ciliate abundance was positively correlated with phosphate, silicate, and pico-sized pigmented eukaryotes (PPEs), whereas the biomass was closely related with PPEs, heterotrophic nanoflagellates, and chlorophytes. The combination of silicate and pigmented nanoflagellates was identified as the major factor driving the ciliate community composition. The close relationship between silicate and ciliate abundance and community structure needs further validation based on more data collected from oceanic waters. Our study showed the necessity of using techniques that can reveal the community composition at higher taxonomic resolutions in future studies on ciliates.
Marine urease with higher thermostability, pH and salinity tolerance from marine sponge-derived Penicillium steckii S4-4
Changrong Liu, Yao Xiao, Yilin Xiao, Zhiyong Li
, Available online  , doi: 10.1007/s42995-020-00076-6
Abstract(69) HTML PDF Springerlink
Urease has a broad range of applications, however, the current studies on urease mainly focus on terrestrial plants or microbes. Thus, it is quite necessary to determine if marine-derived ureases have different characteristics from terrestrial origins since the finding of ureases with superior performance is of industrial interest. In this study, the marine urease produced by Penicillium steckii S4-4 derived from marine sponge Siphonochalina sp. was investigated. This marine urease exhibited a maximum specific activity of 1542.2 U mg protein-1. The molecular weight of the enzyme was 183 kDa and a single subunit of 47 kDa was detected, indicating that it was a tetramer. The N-terminal amino acid sequence of the urease was arranged as GPVLKKTKAAAV with greatest similarity to that from marine algae Ectocarpus siliculosus. This urease exhibited a Km of 7.3 mmol L-1 and a Vmax of 1.8 mmol urea min-1 mg protein-1. The optimum temperature, pH and salinity are 55 ℃, 8.5 and 10%, respectively. This urease was stable and more than 80% of its maximum specific activity was detected after incubating at 25-60 ℃ for 30 min, pH 5.5-10.0 or 0-25% salinity for 6 h. Compared with the terrestrial urease from Jack bean, this marine urease shows higher thermostability, alkaline preference and salinity tolerance, which extends the potential application fields of urease to a great extent.
Roussoelins A and B: two phenols with antioxidant capacity from ascidian-derived fungus Roussoella siamensis SYSU-MS4723
Senhua Chen, Hongjie Shen, Yanlian Deng, Heng Guo, Minghua Jiang, Zhenger Wu, Huimin Yin, Lan Liu
, Available online  , doi: 10.1007/s42995-020-00066-8
Abstract(73) HTML PDF Springerlink
Ascidian-derived microorganisms are a significant source of pharmacologically active metabolites with interesting structural properties. When discovering bioactive molecules from ascidian-derived fungi, two new phenols, roussoelins A (1) and B (2), and ten known polyketides (312) were isolated from the ascidian-derived fungus Roussoella siamensis SYSU-MS4723. The planar structure of compounds 1 and 2 was established by analysis of HR-ESIMS and NMR data. The conformational analysis of the new compounds was assigned according to coupling constants and selective gradient NOESY experiments, and absolute configurations were completed by the modified Mosher's method. Among the isolated compounds, 1, 2, and 9 showed moderate antioxidant capacity.
FACS-iChip: a high-efficiency iChip system for microbial 'dark matter' mining
Haoze Liu, Ran Xue, Yiling Wang, Erinne Stirling, Shudi Ye, Jianming Xu, Bin Ma
, Available online  , doi: 10.1007/s42995-020-00067-7
Abstract(46) HTML PDF Springerlink
The isolation chip method (iChip) provides a novel approach for culturing previously uncultivable microorganisms; this method is currently limited by the user being unable to ensure single-cell loading within individual wells. To address this limitation, we integrated flow cytometry-based fluorescence-activated cell sorting with a modified iChip (FACS-iChip) to effectively mine microbial dark matter in soils. This method was used for paddy soils with the aim of mining uncultivable microorganisms and making preliminary comparisons between the cultured microorganisms and the bulk soil via 16S rRNA gene sequencing. Results showed that the FACS-iChip achieved a culture recovery rate of almost 40% and a culture retrieval rate of 25%. Although nearly 500 strains were cultured from 19 genera with 8 FACS-iChip plates, only six genera could be identified via 16S rRNA gene amplification. This result suggests that the FACS-iChip is capable of detecting strains in the currently dead spaces of PCR-based sequencing technology. We, therefore, conclude that the FACS-iChip system provides a highly efficient and readily available approach for microbial 'dark matter' mining.
The insect-killing bacterium Photorhabdus luminescens has the lowest mutation rate among bacteria
Jiao Pan, Emily Williams, Way Sung, Michael Lynch, Hongan Long
, Available online  , doi: 10.1007/s42995-020-00060-0
Abstract(159) HTML PDF Springerlink
Mutation is a primary source of genetic variation that is used to power evolution. Many studies, however, have shown that most mutations are deleterious and, as a result, extremely low mutation rates might be beneficial for survival. Using a mutation accumulation experiment, an unbiased method for mutation study, we found an extremely low base-substitution mutation rate of 5.94×10-11 per nucleotide site per cell division (95% Poisson confidence intervals: 4.65×10-11, 7.48×10-11) and indel mutation rate of 8.25×10-12 per site per cell division (95% confidence intervals: 3.96×10-12, 1.52×10-11) in the bacterium Photorhabdus luminescens ATCC29999. The mutations are strongly A/T-biased with a mutation bias of 10.28 in the A/T direction. It has been hypothesized that the ability for selection to lower mutation rates is inversely proportional to the effective population size (drift-barrier hypothesis) and we found that the effective population size of this bacterium is significantly greater than most other bacteria. This finding further decreases the lower-bounds of bacterial mutation rates and provides evidence that extreme levels of replication fidelity can evolve within organisms that maintain large effective population sizes.
Report of epibenthic macrofauna found from Haima cold seeps and adjacent deep-sea habitats, South China Sea
Dong Dong, Xinzheng Li, Mei Yang, Lin Gong, Yang Li, Jixing Sui, Zhibin Gan, Qi Kou, Ning Xiao, Junlong Zhang
, Available online  , doi: 10.1007/s42995-020-00073-9
Abstract(11) HTML PDF Springerlink
This work reports on a preliminary taxonomic study of epibenthic macroinvertebrates collected or observed by underwater video at the Haima cold seeps and in adjacent deep-sea habitats, including a mud volcano field and Ganquan Plateau, during an expedition in the South China Sea by the Chinese-manned submersible Shenhai Yongshi in May 2018. A total of 41 species belonging to 6 phyla were identified, among which 34 species were collected from the Haima cold seeps. Mollusks and crustaceans that are specialized in reducing habitats were predominant in biotopes of the Haima cold seeps, whereas sponges and cold-water corals and their commensals were prominent in communities of the mud volcano field and the slopes of Ganquan Plateau. The distribution and faunal composition of each taxonomic group are discussed.
Views and Comments
Progress in studies on the diversity and distribution of planktonic ciliates (Protista, Ciliophora) in the South China Sea
Weiwei Liu, Mann Kyoon Shin, Zhenzhen Yi, Yehui Tan
, Available online  , doi: 10.1007/s42995-020-00070-y
Abstract(70) HTML PDF Springerlink
As an important component of microzooplankton, ciliates play a key role in matter cycling and energy flow in marine planktonic ecosystems. Studies of planktonic ciliate have been extensive in the South China Sea (SCS) over the last 20 years. Here, we summarize the recent progress on the diversity and distribution of this group in the SCS. This includes that in: (1) the waters covering the intertidal zone of the northern SCS, most studies have focused on taxonomy, with 71 species collected, identified, and described (with ~ 40% new species); (2) neritic waters distribution patterns have been examined at a regional scale, with ciliates displaying significant spatial variations and seasonal dynamics; (3) in oceanic waters, there has been a focus on ciliate distribution in north, centre, and south regions, where mesoscale physical processes play roles in controlling distributions, and noticeable vertical variations occur. More generally, some studies examine the influences of environment variables on ciliates, and indicate that chlorophyll a concentration is commonly positively correlated with ciliates abundance. In addition, some significant findings are summarized, the limitations of past studies are considered, and recommendations are made for future work on planktonic ciliates in SCS.