The chromosomal-level genome assembly and annotation of Phyllospadix iwatensis (Surfgrass)

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.