Diversity, abundance, and expression of proteorhodopsin genes in the northern South China Sea.

Proteorhodopsins have been suggested as an important strategy among phototrophs to capture solar energy in marine environments. The goals of this study was to investigate the diversity of proteorhodopsin genes and to explore their abundance, distribution, and expression in the coastal surface waters of the northern South China Sea, one of the largest marginal seas of the western North Pacific Ocean. Using 21 metagenomes, we recovered proteorhodopsin genes from a wide range of prokaryotic taxa, and chlorophyll a contributed significantly to the community composition of proteorhodopsin-containing microbes. Most proteorhodopsin sequences were predicted to encode green light-absorbing proton pumps and green light-absorbing proteorhodopsin genes were more abundant than blue-absorbing ones. The variations in the conserved residues involved in ion pumping and several uncharacterized proteorhodopsins were observed. The gene abundance pattern of proteorhodopsin types were significantly influenced by the levels of total organic carbon and soluble reactive phosphorus. Gene expression analysis confirmed the importance of proteorhodopsin-based phototrophy and revealed different expressional patterns among major phyla. In tandem, we screened 2295 metagenome-assembled genomes to describe the taxonomic distribution of proteorhodopsins. Bacteroidota are the key lineages encoding proteorhodopsins, but proteorhodopsins were predicated from members of Proteobacteria, Marinisomatota, Myxococcota, Verrucomicrobiota and Thermoplasmatota. Our study expanded the diversity of proteorhodopsins and improve our understanding on the significance of proteorhodopsin-mediated phototrophy in the marine ecosystem.

Spatio-temporal dynamics of phytoplankton community structure in the coastal waters of the Southern Beibu Gulf.

This study was conducted during October 2021 (autumn) and April 2022 (spring) to explore the phytoplankton community structure, their distribution characteristics, and the influence of environmental factors in the coastal waters of the Southern Beibu Gulf. The 15 sampling sites were grouped based on the difference in offshore distance to analyze the temporal and spatial differences in community structure and environmental driving in the investigated sea area of the coastal waters of the Southern Beibu Gulf. Permutational multivariate analysis of variance was conducted on the sample data in time and space, revealing that there is no significant difference in space (p > 0.05), but there is significant difference in time (p < 0.05). Notably, water pressure, pH, chemical oxygen demand, nitrite, and labile phosphate were higher in autumn, while total ammonia nitrogen, dissolved oxygen, and suspended solids were significantly higher in spring. Additionally, the study identified 87 phytoplankton species belonging to 6 phyla, dominating by Bacillariophyta, followed by Dinophyta and Cyanophyta. The phytoplankton density, Shannon Weiner's diversity index (H'), Pielou's evenness index (J), and Margalef's richness index (D) ranged from 84.88 to 4675.33 cells L-1, 0.56 to 2.58, 0.26 to 0.89, and 1.21 to 3.64, respectively. Permutational multivariate analysis of variance showed non-significant spatial differences in phytoplankton composition (p > 0.05) but seasonal differences (p < 0.05). Furthermore, canonical correspondence analysis (CCA) identified pH, dissolved oxygen, suspended solids, chemical oxygen demand, nitrite, and labile phosphate as key environmental factors influencing the phytoplankton community structure (p < 0.05). In this study, the dynamic changes of phytoplankton community structure and environmental factors in the southern coastal waters of Beibu Gulf were analyzed in detail from two aspects of time and space. The key environmental factors to protect the ecological environment in the southern coastal area of Beibu Gulf were found out. It provides a reference method and theoretical basis for the management and protection of Beibu Gulf and other tropical marine environment.

Distribution patterns of reef-building corals in the Northwest Pacific and their environmental drivers.

Understanding species distribution and the related driving processes is a fundamental issue in ecology. However, incomplete data on reef-building corals in the ecoregions of the South China Sea have hindered a comprehensive understanding of coral distribution patterns and their ecological drivers in the Northwest Pacific (NWP). This study investigated the coral species diversity and distribution patterns in the NWP by collecting species presence/absence data from the South China Sea and compiling an extensive species distribution database for the region, and explored their major environmental drivers. Our NWP coral database included 612 recorded coral species across 15 ecoregions. Of these, 536 coral species were recorded in the South China Sea Oceanic Islands after compilation, confirming the extraordinary coral species diversity in this ecoregion. Coral alpha diversity was found to decrease with increasing latitude in the whole NWP, while the influence of the Kuroshio Current on environmental conditions in its path results in a slower decline in species richness with latitude compared to regions within the South China Sea. Beta-diversity decomposition revealed that nestedness patterns mainly occurred between low and high latitude ecoregions, while communities within similar latitudes exhibited a turnover component, particularly pronounced at high latitudes. The impact of environmental factors on coral assemblage structure outweighed the effects of spatial distance. Temperature, especially winter temperature, and light intensity strongly influenced alpha diversity and beta diversity's nestedness component. Additionally, turbidity and winter temperature variations at high latitudes contributed to the turnover pattern observed among communities in the NWP. These findings elucidate the assembly processes and major environmental drivers shaping different coral communities in the NWP, highlighting the significant role of specific environmental filtering in coral distribution patterns and providing valuable insights for coral species conservation efforts.

Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia.

Four new species of Marphysa are described from Terengganu state on the east coast of Peninsular Malaysia, using morphological and molecular (cytochrome oxidase subunit I (COI) gene) data. These species belong to different groups of Marphysa: Marphysakertehensis sp. nov. belongs to Group A (Mossambica), Marphysamerchangensis sp. nov. and Marphysasetiuense sp. nov. belong to Group B (Sanguinea) and Marphysaibaiensis sp. nov. belongs to Group E (Gravelyi). Marphysakertehensis sp. nov. is characterised by having only limbate chaetae, absence of subacicular hooks, three types of pectinate chaetae including wide, thick isodont with short and slender inner teeth, and pectinate branchiae with up to nine branchial filaments. Marphysamerchangensis sp. nov. is characterised by the presence of eyes, unidentate subacicular hooks, four types of pectinate chaetae including wide, thick anodont pectinate chaetae with five long and thick inner teeth, and pectinate branchiae with up to six branchial filaments. Marphysasetiuense sp. nov. has mostly unidentate subacicular hooks (bidentate on several posterior chaetigers), four types of pectinate chaetae including wide, thick anodont pectinate chaetae with seven thick and long inner teeth, and pectinate branchiae with up to five branchial filaments. Marphysaibaiensis sp. nov. has bidentate subacicular hooks throughout, five types of pectinate chaetae, including a heterodont with 12 short and slender inner teeth, and pectinate branchiae with up to eight branchial filaments. The designation of these new species based on morphology is fully supported by molecular data. Habitat descriptions of each species are also included.

Organophosphate ester in surface water of the Pearl River and South China Sea, China: Spatial variations and ecological risks.

This study focused on investigating the concentrations, compositional profiles, partitioning behaviors and spatial variations of organophosphate esters (OPEs) in the Pearl River (PR), South China Sea (SCS) region, to evaluate their environmental risks. ∑OPEs concentrations in the surface water of the PR ranged from 117.5 to 854.8 ng/L in the dissolved phase and from 0.5 to 13.3 ng/L in the suspended particulate matter. In the surface seawaters of the northern and western parts of the SCS, ∑OPEs concentrations were 1.3-17.6 ng/L (mean: 6.7 ± 5.2) and 2.3-24.4 ng/L (mean: 7.6 ± 5.5), respectively. The percentage of chlorinated OPEs in surface water samples from the PR to the SCS was 79 ± 15%. Tripentyl phosphate (TPeP) (average: 28.3%) and triphenylphosphate (TPhP) (average: 9.6%) exhibited significant particulate fraction. A significant negative correlation (p < 0.05) between salt concentration and OPE congeners in seawater suggested that river runoff predominantly introduced OPEs into the coastal waters of the SCS. The findings also showed higher levels of OPEs in the PR and estuary than in offshore waters. The OPE loading from the PR into the SCS was estimated to be ∼119 t y-1. The presence of TCEP (RQmax = 2.1), TnBP (RQmax = 0.48) and TPhP (RQmax = 0.3) in PR water samples pose a high risk to aquatic organisms, whereas OPEs (RQ < 0.1) in SCS water samples do not pose a threat to aquatic organisms. This research emphasizes the environmental fate and impact of OPEs on surface waters of the PR and SCS.

Species diversity of fish at the Wuzhizhou Island, South China Sea, based on environmental DNA.

Background: Wuzhizhou Island (WZZ) is located in Haitang Bay in the northern region of Sanya, Hainan Island. The sea area surrounding WZZ represents a typical tropical marine ecosystem, characterised by diverse and complex habitats. Therefore, there is a rich variety of marine fish species at WZZ. The marine ecosystem of WZZ was seriously destroyed initially in the 1970s-1980s and recovered in the 1990s, then constructed as the first national tropical marine ranch demonstration area of China in 2019. As fish is an important high trophic vertebrate in the marine ecosystem, understanding the composition and distribution of fish species could help us to recognise the status of the ecosystem of WZZ and supply scientific data for construction of the national marine ranch demonstration area. This study used eDNA technology to investigate the composition of fish community surrounding WZZ and provided a scientific basis for realising and protecting the marine ecosystem of the South China Sea. New information: The WZZ is an offshore island in the South China Sea, harbouring abundant marine fish resources. Although previous research investigated fish species of WZZ, the data were, however, still incomplete due to limitation of sampling methods and survey seasons. In this study, we intended to take advantage of eDNA and supplement data of fish species at WZZ as much as possible. Based on eDNA, this study provided the data on 188 fish species (including nine undetermined species denoted by genus sp.) belonging to 17 orders, 63 families and 124 genera and they were the more comprehensive records of fish species surrounding WZZ. In addition, the information on Molecular Operational Taxonomic Units (MOTUs) for taxon identification was also provided, aiming to contribute to the establishment of a specific eDNA taxon database for fish of the South China Sea. This study included two datasets, which were occurrences of fish taxa at WZZ, as well as MOTUs sequences and geographical coordinate information of sampling sites. The "fish taxon occurrences" dataset presented records on taxonomic, distribution and habitat conditions of 188 fish species detected using eDNA, as well as the latitude and longitude information of the sampling sites, the "MOTUs information" dataset provided the MOTUs sequences, source of sequences, abundance of sequences for 188 fish species, also included the species matched in NCBI and the best NCBI BLAST sequence similarity.

Okeanomitos corallinicola gen. and sp. nov. (Nostocales, Cyanobacteria), a new toxic marine heterocyte-forming Cyanobacterium from a coral reef.

Cyanobacterial mats supplanting coral and spreading coral diseases in tropical reefs, intensified by environmental shifts caused by human-induced pressures, nutrient enrichment, and global climate change, pose grave risks to the survival of coral ecosystems. In this study, we characterized Okeanomitos corallinicola gen. and sp. nov., a newly discovered toxic marine heterocyte-forming cyanobacterium isolated from a coral reef ecosystem of the South China Sea. Phylogenetic analysis, based on the 16S rRNA gene and the secondary structure of the 16S-23S rRNA intergenic region, placed this species in a clade distinct from closely related genera, that is, Sphaerospermopsis stricto sensu, Raphidiopsis, and Amphiheterocytum. The O. corallinicola is a marine benthic species lacking gas vesicles, distinguishing it from other members of the Aphanizomenonaceae family. The genome of O. corallinicola is large and exhibits diverse functional capabilities, potentially contributing to the resilience and adaptability of coral reef ecosystems. In vitro assays revealed that O. corallinicola demonstrates notable cytotoxic activity against various cancer cell lines, suggesting its potential as a source of novel anticancer compounds. Furthermore, the identification of residual saxitoxin biosynthesis function in the genome of O. corallinicola, a marine cyanobacteria, supports the theory that saxitoxin genes in cyanobacteria and dinoflagellates may have been horizontally transferred between them or may have originated from a shared ancestor. Overall, the identification and characterization of O. corallinicola provides valuable contributions to cyanobacterial taxonomy, offering novel perspectives on complex interactions within coral reef ecosystems.

Prevention policies for the marine ecological environment in the South China Sea as a consequence of excessive plastic compound use in Vietnam.

Vietnam suffers from a distressing predicament: It ranks among the most heavily contaminated nations on earth. Its coastal and marine domains are plagued by an excess of plastic waste. Vietnam has consistently discharged a substantial amount of waste into the oceans, ranging from 0.28 to 0.73 million metric tons annually. Numerous areas have emerged as focal points of plastic pollution throughout its extensive seashore and marine areas. The escalating presence of marine litter poses an increasingly grave threat to the intricate equilibrium of Vietnam's marine ecosystems. This comprehensive policy study reveals that the mounting problem of ocean plastic pollution, characterized by the abundance of floating plastic debris, imperils both plant and animal life, placing various marine species such as seabirds, fish, turtles, and cetaceans at risk. The consumption of minuscule plastic particles and the harmful impact of chemical pollutants from plastic waste in the ocean not only endangers the vitality of marine life but also poses a substantial hazard to human well-being because plastic waste infiltrates the food chain. This research reveals that, despite the existence of numerous laws and policies-including the Law on Environmental Protection 2020, the Marine Plastic Waste Management Initiative for the Fisheries Sector 2020-2030, and the National Action Plan for Management of Marine Plastic Litter-a significant amount of plastic waste is infiltrating the river network and eventually infiltrating oceans as a result of improper monitoring and ineffective enforcement of these legislations. Relying primarily on existing data released by the government and other sources and a wide range of gray literature retrieved from reputable databases, this study aims to evaluate the role of Vietnam's legal framework for combating the critical issue of marine plastic pollution in the South China Sea. Integr Environ Assess Manag 2024;00:1-19. © 2024 SETAC.

Inventorization and ecological risk assessment of tetrabromobisphenol A and hexabromocyclododecane in sediments from Guangdong coastal area of South China Sea.

Brominated flame retardants (BFRs) exhibit excellent flame retardant properties and are widely used in various industries. Among the common BFRs, tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCDs) pose substantial ecological and human health risks due to their extensive application and long-range transport. This study established 131 sample collection sites along the coast of the South China Sea (SCS) in Guangdong Province to assess the concentration, distribution, inventory, and ecological risk of TBBPA and HBCDs in surface sediments. The concentrations of TBBPA in SCS sediments ranged from < limit of detection (LOD) to 80 µg/kg dry weight (dw), and those of HBCDs from < LOD to 18 µg/kg dw. The diastereoisomers of HBCDs (α-, ß-, and γ-HBCD) in the sediment samples accounted for 36 %, 13 %, and 51 %, respectively. Human activities, particularly those associated with nearby electronic waste disassembly and textile and garment industries, considerably influenced the dispersion of TBBPA and HBCDs. The inventories of TBBPA and HBCDs in Guangdong Province's SCS were estimated to be 3.2 × 105 kg and 7.2 × 104 kg, respectively. The average risk quotient values ranged from <0.01 to 0.016, indicating a low to negligible environmental risk. This study provides deeper insights into the distribution and scientific significance of HBCDs and TBBPA in SCS sediment samples, elucidates the current state of BFR contamination, and offers recommendations for future research on environmental safety and human health in the region.

Seagrass repression by green turtles (Chelonia mydas) around Taiping Island in the south China sea: Experimental evidence and management insights.

Seagrass meadows serve as critical marine habitats, offering numerous benefits to both humans and wildlife. Taiping Island, situated in the South China Sea, has been historically known for its abundant seagrass meadows. However, satellite imagery suggested there was a low density of seagrasses around Taiping Island. On the other hand, many green turtles (Chelonia mydas) were observed from the shore. To investigate this phenomenon, we conducted drone surveys of the shallow reefs and discovered a density of 902 ± 601 (mean ± SD) individual turtles per square kilometer during high tides. In addition, we conducted a cage experiment to test the hypothesis that large herbivores are impacting seagrass abundance negatively. The results indicated that the blade lengths of seagrasses in cages were significantly longer than those outside. It is likely that large herbivores such as green sea turtles are the key consumers of seagrass on the shallow reef flats of Taiping Island. Accordingly, further research and management should take into account that the increasing number of sea turtles may deplete the seagrasses and have an impact on the seagrass ecosystems.

Deep-sea caridean shrimps collected from the South China Sea with emphasizing their phylogenetic relationships.

Despite the high biological and ecological diversity of the South China Sea, limited research has been conducted on the deep-sea species diversity of caridean shrimps. Based on the collections from three scientific expeditions conducted in the South China Sea, 31 caridean species, belonging to nine families, were reported, including the identification of two species not previously documented in this region, namely Janicella spinicauda (A. Milne-Edwards, 1883) and Systellaspis curvispina Crosnier, 1988. In addition to morphological features, the COI and 16S gene sequences of these species were analyzed to assess their evolutionary relationships within each family. Phylogenetic analyses, with highest species coverage to date, indicated that similarity in morphological characteristics does not always lead to closer phylogenetic relationships and some defining characteristics for specific taxa are not always synapomorphies but may be the result of convergent evolution. Our results establish reliable evolutionary relationships within specific taxa and highlight the necessity for further taxonomic revisions within these taxa.

A New Species of the Genus Takydromus (Squamata: Lacertidae) from Northeastern Guangxi, China.

During our collecting trip to Guangxi in 2016, we collected ten specimens of the genus Takydromus from the suburb of Guilin, northeastern Guangxi, South China, and found that they did not belong to any currently known species. Here, we described this new species, Takydromus guilinensis sp. nov., based on morphological and mitochondrial DNA (CO1 and cyt b) data. This new species is a sister taxon to T. intermedius with a p-distance of 0.070 in CO1 and 0.080 in cyt b. These two p-distances exceed not only the minimum value (0.067) between T. septentrionalis and T. stejnegeri but also the minimum value (0.079) between T. intermedius and T. yunkaiensis. Morphologically, this new species differs from other currently recognized Takydromus species from the same clade, more evidently in the longitudinal rows of dorsal scales, transverse rows of scales at the mid-body and mensural variables. The description of Takydromus guilinensis sp. nov. increases the total number of Takydromus species to 25, of which 16 can be found in China. Takydromus guilinensis sp. nov. is currently known only from Guilin, Guangxi, South China, where it is sympatric with the other four Takydromus species (T. septentrionalis, T. kuehnei, T. sexlineatus and T. intermedius).

Aquaculture Performance and Genetic Diversity of a New [(Crassostrea hongkongensis ♀ × C. gigas ♂) ♂ × C. hongkongensis ♀] Variety of the Oyster "South China No. 1" in Beibu Gulf, China.

Crassostrea hongkongensis is an economically important bivalve found in various parts of the South China Sea. A new interspecific backcross ([(Crassostrea hongkongensis ♀ × C. gigas ♂) ♂ × C. hongkongensis ♀]) variety was bred by the South China Sea Institute of Oceanology which named "South China No. 1". This study aims to explore the effects of stocking density on the growth performance of "South China No. 1", compared their growth performance and genetic diversity to C. hongkongensis, and found the best place breeding site for "South China No. 1" in Beibu Gulf. The results showed that stocking a density of 20 oysters/substrate can significantly increase the shell height, shell width, total weight, survival rate, daily shell height gain and daily body mass gain. It was found that the shell height and total weight of "South China No. 1" cultured in Fangchenggang were significantly higher than that of those in Beihai and Qinzhou from September 2018 to November 2018. Similarly, the shell width of oysters in Fangchenggang and Qinzhou was also significantly higher in September 2018, and the interaction between site and stocking density had significant effects on the shell width in March 2018 and November 2018. In addition, the shell height and shell width of "South China No. 1" were significantly higher than that of C. hongkongensis in all three sites. At all three sites, the phytoplankton community structure was mostly dominated by Bacillariophyta. In the Hardy-Weinberg equilibrium test, for the seven populations and ten microsatellites, in 10 of the 70 groups, the segregation distortion was significant. These results suggest that a stocking density of 20 oysters/substrate can promote the shell height, shell width and total weight of "South China No. 1" in Beibu Gulf, China. "South China No. 1" has better growth performance compared with C. hongkongensis. Fangchenggang is a suitable place to cultivate the "South China No. 1" breed according to the total weight and sum of all algal genus abundances. The results of this study can be used as a reference to further understand the stocking density and genetic diversity of the "South China No. 1" breed in Beibu Gulf, China.

Genome analysis of Rossellomorea sp. y25, a deep sea bacterium isolated from the sediments of South China Sea.

Rossellomorea sp. y25, a putative new species of yellow pigment-producing, aerobic and chemoheterotrophic bacterium belonging to the family Bacillaceae, was isolated from the sediments at the depth of 1829 m in the South China Sea. In this study, we present the complete genome sequences of strain y25, which consisted of only one circular chromosome with 4,633,006 bp and the content of G + C was 41.76%. A total of 4466 CDSs, 106 tRNA, 33 rRNA, and 101 sRNA genes were obtained. Genomic analysis of strain y25 showed that it has the ability to produce antioxidant carotenoids and a large number of heavy metal resistance genes, such as arsenic, cadmium and zinc. In addition, strain y25 contains a prophage that may contribute to host protection against lysis by related Bacillus-like phages. This is the first report of genome-wide information on a bacterium of the genus Rossellomorea isolated from the deep sea, providing insights into how microorganisms of this genus adapt to deep-sea environments.

A large-scale comparison of the meat quality characteristics of different chicken breeds in South China.

Meat quality traits are essential for producing high-quality broilers, but the genetic improvement has been limited by the complexity of measurement methods and the numerous traits involved. To systematically understand the meat quality characteristics of different broiler breeds, this study collected data on slaughter performance, skin color, fat deposition, and meat quality traits of 434 broilers from 12 different breeds in South China. The results showed that there was no significant difference in the live weight and slaughter weight of various broiler breeds at their respective market ages. Commercial broiler breeds such as Xiaobai and Huangma chickens had higher breast muscle and leg muscle rates. The skin and abdominal fat of Huangma chickens cultivated in the consumer market in South China exhibited significantly higher levels of yellowness compared to other varieties. Concerning fat traits, we observed that Wenchang chickens exhibited a strong ability to fat deposition, while the younger breeds showed lower fat deposition. Additionally, there were significant positive correlations found among different traits, including traits related to weight, traits related to fat, and skin color of different parts. Hierarchical clustering analysis revealed that fast-growing and large broiler Xiaobai chickens formed a distinct cluster based on carcass characteristics, skin color, and meat quality traits. Principal component analysis (PCA) was used to extract multiple principal components as substitutes for complex meat quality indicators, establishing a chicken meat quality evaluation model to differentiate between different breeds of chickens. At the same time, we identified 46, 22, and 20 SNP loci and their adjacent genes that were significantly associated with muscle mass traits, fat deposition, and skin color through genome-wide association studies (GWAS). The above results are helpful for systematically understanding the differences and characteristics of meat quality traits among different breeds.

Genetic characteristics and selection signatures between Southern Chinese local and commercial chickens.

The introduction of exotic breeds and the cultivation of new lines by breeding companies have posed challenges to native chickens in South China, including loss of breed characteristics, decreased genetic diversity, and declining purity. Understanding the population genetic structure and genetic diversity of native chickens in South China is crucial for further advancements in breeding efforts. In this study, we analyzed the population genetic structure and genetic diversity of 321 individuals from 10 different breeds in South China. By comparing commercial chickens with native ones, we identified selection signatures occurring between local chickens and commercial breeds. The analysis of population genetic structure revealed that the native chicken populations in South China exhibited a considerable level of genetic diversity. Moreover, the commercial lines of Xiaobai chicken and Huangma chicken displayed even higher levels of genetic diversity, which distinguished them from other native varieties at the clustering level. However, certain individuals within these commercial varieties showed a discernible genetic relationship with the native populations. Notably, both commercial varieties also retained a significant degree of genetic similarity to their respective native counterparts. In order to investigate the genomic changes occurring during the commercialization of native chickens, we employed 4 methods (Fst, ROD, XPCLR, and XPEHH) to identify potential candidate regions displaying selective signatures in Southern Chinese native chicken population. A total of 168 (identified by Fst and ROD) and 86 (identified by XPCLR and XPEHH) overlapping genes were discovered. Functional annotation analysis revealed that these genes may be associated with reproduction and growth (SAMSN1, HYLS1, ROBO3, FGF14, PRSS23), musculoskeletal development (DNER, MYBPC1, DGKB, ORC1, KLF10), disease resistance and environmental adaptability (PUS3, CRB2, CALD1, USP15, SGCD, LTBP1), as well as egg production (ADGRB3, ACSF3). Overall, native chickens in South China harbor numerous selective sweep regions compared to commercial chickens, enriching valuable genomic resources for future genetic research and breeding conservation.

New species and records of Hybos Meigen (Diptera, Empidoidea) from Huaping National Nature Reserve, China.

In this study, 21 species of Hybos Meigen, 1803 are reviewed in Huaping National Nature Reserve, China. Among these, three species, i.e., Hybosdenticulatussp. nov., Hybosforcipatasp. nov. and H.paraterminalissp. nov., are described as new to science. In addition, nine known species of this genus are reported for the first time in Guangxi. All the known species were enumerated, and an identification key to the species of Hybos from Huaping National Nature Reserve based on morphological characteristics is provided.

Flagellimonas halotolerans sp. nov., a novel bacterium isolated from the South China Sea.

Two Gram-stain-negative strains, designed SYSU M86414T and SYSU M84420, were isolated from marine sediment samples of the South China Sea (Sansha City, Hainan Province, PR China). These strains were aerobic and could grow at pH 6.0-8.0 (optimum, pH 7.0), 4-37 °C (optimum, 28 °C), and in the presence of 0-10 % NaCl (w/v; optimum 3 %). The predominant respiratory menaquinone of strains SYSU M86414T and SYSU M84420 was MK-6. The primary cellular polar lipid was phosphatidylethanolamine. The major cellular fatty acids (>10 %) in both strains were iso-C15 : 0, iso-C15 : 1 G, and iso-C17 : 0 3-OH. The DNA G+C content of strains SYSU M86414T and SYSU M84420 were both 42.10 mol%. Phylogenetic analyses based on 16S rRNA gene sequences and core genes indicated that these novel strains belonged to the genus Flagellimonas and strain SYSU M86414T showed the highest 16S rRNA gene sequence similarity to Flagellimonas marinaquae JCM 11811T (98.83 %), followed by Flagellimonas aurea BC31-1-A7T (98.62 %), while strain SYSU M84420 had highest 16S rRNA gene sequence similarity to F. marinaquae JCM 11811T (98.76 %) and F. aurea BC31-1-A7T (98.55 %). Based on the results of polyphasic analyses, strains SYSU M86414T and SYSU M84420 should be considered to represent a novel species of the genus Flagellimonas, for which the name Flagellimonas halotolerans sp. nov. is proposed. The type strain of the proposed novel isolate is SYSU M86414T (=GDMCC 1.3806T=KCTC 102040T).

First record of the hippolytid shrimp Hippolyteaustraliensis (Stimpson, 1860) (Crustacea, Decapoda) from China.

Background: Two specimens of the genus Hippolyte were examined from the caridean collections of the Marine Biological Museum, Chinese Academy of Sciences. These specimens were captured in the South China Sea in 1987. Detailed inspection revealed that their morphological features closely match the (re)descriptions of Hippolyteaustraliensis, especially in the presence of a long, distinct lateral carina on the rostrum, a dorsally unarmed rostral border, and four prominent terminal spines on the dactylus of the last three pereiopods. New information: The discovery of Hippolyteaustraliensis in Chinese waters represents a significant expansion of its geographic distribution from the South Pacific to the North Pacific. Furthermore, an additional taxonomical report of H.australiensis is provided since its retrieval in 2001.