Abstract
Phyllospadix iwatensis is a unique seagrass species adapted to rocky substrate anchorage and dioecy and belongs to marine submerged flowering plants with a distinctive evolutionary history. The chromosomal-scale genome was constructed by integrating Illumina, PacBio HiFi, and high-throughput chromosome conformation capture (Hi-C) sequencing techniques. A total of 340.56 Mb of sequences were anchored to 10 chromosomes with an anchoring rate of 96.44%. The contig and scaffold N50 values reached 30.64 Mb and 33.59 Mb, respectively. Precisely 94.64% of the 23,198 predicted protein-coding genes received functional annotation. In the meantime, 180.19 Mb of repetitive sequences were found, representing 52.91% of the assembled genome. The chromosomal-level genome data of P. iwatensis will reveal its special process of differentiation and enrich the understanding of the multiple adaptations of seagrass populations to marine habitats.
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Data availability
The complete dataset of P. iwatensis, including raw sequencing data (Illumina, PacBio, Hi-C, and RNA sequencing reads) and the assembled genome, is publicly available via the following repositories:
NCBI SRA:
https://identifiers.org/ncbi/insdc.sra:SRR34629676
https://identifiers.org/ncbi/insdc.sra:SRR34629675
https://identifiers.org/ncbi/insdc.sra:SRR34629674
https://identifiers.org/ncbi/insdc.sra:SRR34629673
NCBI GenBank: https://identifiers.org/ncbi/insdc:JBTXFO000000000.1
Code availability
All bioinformatics analyses in this study were performed in strict accordance with the guidelines of the respective tools. No custom scripts were developed; all operations adhered to the standard protocols of the employed software. These tools are publicly accessible, with detailed information on their versions and parameter settings provided in the Methods section.
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Acknowledgements
This reaserch was supported by the National Natural Science Foundation of China (NO. 42476112) and the Shandong Provincial Bureau of Geology and Mineral Resources project (NO. HJ202510).
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L.Z.N. and Z.Q.S. conceived and designed the study, secured funding, and participated in manuscript writing, review, and editing. W.D.W. and Z.K. conducted the experiments and analyzed the data. W.J.Y. analyzed the data and drafted the initial manuscript. All authors reviewed and approved the final version of the manuscript.
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Wang, J., Wang, D., Zhao, K. et al. The chromosomal-level genome assembly and annotation of Phyllospadix iwatensis (Surfgrass). Sci Data (2026). https://doi.org/10.1038/s41597-026-06911-2
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DOI: https://doi.org/10.1038/s41597-026-06911-2
