Bingpeng Xing

Coralline algae are important calcifying red algae that contribute substantially to marine ecosystem structure and biogenic reef formation. However, their species diversity and geographic distribution in China remain poorly documented due to their extensive calcification, morphological convergence, and ongoing revisions of taxonomic frameworks. In this study, we reviewed published Chinese and English literature from 1980 to 2026 using Web of Science and the China National Knowledge Infrastructure (CNKI), with the literature search completed on 2 July 2026. By integrating species records, taxonomic revisions, and regional distribution data, we assessed the diversity and spatial distribution patterns of coralline algae in China. Historical records were revised by incorporating updated taxonomic information, including corrections of synonyms and taxonomic changes, resulting in an updated and verifiable checklist of accepted species. Our results showed that 109 coralline algal species, belonging to 30 genera, 8 families, and 3 orders, are currently recorded in China. Among these taxa, Corallinales contains the highest species diversity, Corallinaceae represents the most species-rich family, and Jania is the most species-rich genus. Taiwan, Hainan, and Sansha exhibit relatively high species richness, whereas differences among regions may be associated with variations in survey intensity. Spearman correlation analysis revealed a positive relationship between regional publication numbers and recorded species richness, suggesting that current understanding of coralline algal diversity in China remains influenced by sampling effort. This study provides an updated assessment of coralline algal diversity and spatial distribution patterns in China, establishing baseline information for future taxonomic research, biodiversity assessments, and conservation efforts.

The Western Pacific is characterized by high species diversity; however, limited studies have been carried out in the past, particularly in biology, on the West

This study investigates the spatiotemporal dynamics of zooplankton communities in the tropical low-latitude Northwestern Pacific Ocean based on field surveys conducted in August 2021 and November 2022. Redundancy analysis identified nitrate, silicate, temperature, and salinity as the primary factors influencing community structure. The distribution of dominant zooplankton groups exhibited close correlations with key environmental gradients, showing distinct habitat preferences corresponding to different hydrographic conditions. Zooplankton abundance in August 2021 was significantly higher than that in November 2022, which is presumably attributed to eddy-induced nutrient upwelling and enhanced primary productivity. Comparisons with adjacent marine regions reveal general consistency in overall zooplankton abundance and community species composition, while the observed seasonal discrepancies are closely associated with local unique hydrographic characteristics. These results highlight the role of nutrient–temperature–salinity interactions in structuring zooplankton communities and underscore their sensitivity to environmental variability. The findings provide a scientific basis for understanding pelagic ecosystem dynamics in oligotrophic waters and for developing management strategies under changing climate and oceanographic conditions.

In this study, we report the complete mitochondrial genomes of 12 organic-fall mussel species from waters surrounding China, including nine putatively undescribed lineages. By integrating these data with previously published mitochondrial genomes and complementary nuclear markers from vent- and seep-associated taxa, we reconstructed a phylogenetic framework for the subfamily Bathymodiolinae. The results place Vulcanidas and “Lignomodiolus” among relatively early-branching lineages, a pattern that is consistent with evolutionary scenarios such as the “wooden stepping-stone” hypothesis.,In terms of species diversity, we recognized 14 operational taxonomic units (OTUs), four of which are reported here for the first time, thereby expanding the known taxonomic diversity of organic-fall mussels. Furthermore, our observations indicate that organic-fall mussels adopt two main ecological strategies—burrow-dwelling and surface-dwelling—associated with distinct shell morphologies, although both strategies may coexist within a single species.,Selection pressure analyses showed that all mitochondrial protein-coding genes are predominantly subject to purifying selection, particularly cox1–3, reflecting their essential roles in oxidative phosphorylation. In contrast, several nad subunits and cytb exhibited relatively elevated ω values in vent- and seep-dwelling mussels, suggesting potential lineage-specific modulation of mitochondrial function in relation to symbiont-associated metabolism and heterogeneous redox conditions.

Acanthopleura loochooana is a widely distributed intertidal chiton in the northwestern Pacific, yet its mitochondrial genomic architecture and evolutionary position within Chitonidae have not been comprehensively evaluated. In this study, we sequenced and analyzed the complete mitochondrial genome of A. loochooana using next-generation sequencing. The mitogenome is a circular double-stranded DNA molecule of 15,295 bp that contains the typical 37 mitochondrial genes, including 13 protein-coding genes (PCGs), 22 transfer RNA genes, and 2 ribosomal RNA genes. Codon usage patterns show a clear preference for A- or U-ending codons, consistent with trends observed in other polyplacophoran mitogenomes. Phylogenetic analyses based on concatenated sequences of the 13 mitochondrial PCGs under Bayesian frameworks recovered congruent topologies with strong nodal support. A. loochooana was placed in a well-supported clade with Liolophura japonica and A. vaillantii, providing a reference within Acanthopleurinae. These results provide the complete mitochondrial genome of A. loochooana and contribute new mitogenomic data to the currently limited dataset of Polyplacophora, offering additional insights into mitochondrial genome organization and phylogenetic relationships within Acanthopleurinae.

Organic falls play an important role in the evolutionary transition of chemosymbiotic mollusks from shallow to deep seas. Exploring their genetic characteristics is essential to elucidating adaptive mechanisms. Here, we report the first complete mitochondrial genome of Glabracollonia laevigata (Family Colloniidae), collected from sunken wood at 200 m depth in the East China Sea. The circular genome is 18,056 bp in length with an average sequencing depth of 6847×, and contains 13 protein-coding genes (PCGs), two rRNA genes, and 23 tRNA genes, including a duplicated trnY. The nucleotide composition is biased toward A + T (69.0%). Most PCGs use ATG as the start codon, except nad6 (GTG) and nad4L (ATA), and all terminate with TAA or TAG. Codon usage analysis revealed a preference for A and U at the third codon position. Phylogenetic analyses based on concatenated PCGs, using Bayesian inference and maximum likelihood approaches, strongly support a close relationship between Colloniidae and Phasianellidae, consistent with recent studies. These findings offer new insights into the phylogenetic placement of Colloniidae within Trochoidea, while contributing to a broader understanding of biodiversity and evolutionary adaptation in organic-fall ecosystems.

A new species of jellyfish, Phyllorhiza yurena Chen, Hu & Xing sp. nov., is described from the East China Sea based on an integrative approach combining morphological and molecular data. Specimens were collected from coastal waters and cultured in the laboratory to observe their complete life cycle, including polyps, ephyrae, and medusae. Distinct morphological features such as the blue lappet stems in ephyrae, white warts on the exumbrella, and multiple short club-shaped appendages on the mouth arms distinguish the new species from its congeners. Phylogenetic analyses based on mitochondrial (COI, 16S) and nuclear (18S, 28S) gene markers confirmed its taxonomic distinctiveness, with COI and 16S markers providing the most resolution. The study highlights the importance of combining life history observations with molecular tools for accurate jellyfish taxonomy and provides a revised identification key for the genus Phyllorhiza. This discovery contributes to the understanding of jellyfish biodiversity in the East China Sea and offers a baseline for future ecological and biogeographic studies.

Background: The Polyplacophora class, which includes all chitons, is distinguished by its unique eight-piece interlocking armor, showcasing a vast diversity in marine environments. However, the detailed evolutionary relationships within the Chitonidae family remain largely unknown. The mitochondrial genome is essential for understanding these relationships, but there has been a significant lack of such genomic information, especially for the Liolophura genus. Methods: We generated the first mitogenome of Liolophura japonica by assembling Illumina reads with GetOrganelle, polishing with Pilon, annotating genes with MitoZ and MITOS2, and inferring phylogeny from 13 concatenated protein-coding genes (PCGs) using MAFFT and IQ-TREE. Results: The mitogenome is 15,209 base pairs long and includes 13 protein-coding genes, 22 transfer RNAs, and 2 ribosomal RNAs. The mitogenome exhibited a slight AT bias common in Chitonidae and showcased structural uniqueness with no control region found. Notably, all protein-coding genes demonstrated evidence of purifying selection, with Ka/Ks ratios below 1, highlighting evolutionary conservation. Phylogenetic analysis reveals a close relationship between L. japonica, Acanthopleura loochooana Broderip & Sowerby 1829, and Acanthopleura vaillantii Rochebrune, 1882, potentially warranting future taxonomic re-evaluation. This research emphasizes the crucial role of mitochondrial genomes in mollusk phylogeny and sets the stage for advanced genetic studies within this group. Conclusions: The significance of this study lies in its contribution to understanding the mitochondrial genome of L. japonica, a key species within the Polyplacophora class. By analyzing its mitogenome, we aim to enhance our understanding of evolutionary processes in chitons and other mollusks.

Mussels of the genus Idas (Bathymodiolinae) are small bivalves inhabiting organic falls and cold seep ecosystems. Despite their ecological significance, the taxonomy and phylogeny of Idas remain understudied. In this study, 30 Idas specimens were collected from a piece of sunken wood in the East China Sea at depths of 460–550 m. DNA barcoding and phylogenetic analysis revealed three distinct clades: 23 specimens matched Idas sp. ESU D, previously reported from Japan and the Philippines, five samples clustered with Idas iwaotakii (Habe, 1958), and two samples formed a new clade related to I. iwaotakii. These findings resulted in the description of two new species, Idas sinensissp. nov. and Idas pacificussp. nov. We present the complete mitochondrial genomes for both species and investigate the diversity of their symbiotic microbes through full-length 16S rRNA amplicon sequencing. Phylogenetic analyses of mitochondrial genomes further support the taxonomic placement of the new species. The gill-associated microbial communities of these mussels include sulfur-oxidizing SUP05 bacteria, suggesting chemosynthetic symbiosis.