Abstract Chitons (Polyplacophora) are marine molluscs that can be found worldwide from cold waters to the tropics, and play important ecological roles in the environment. Nevertheless, there remains only two chiton genomes sequenced to date. The chiton Liolophura japonica (Lischke, 1873) is one of the most abundant polyplacophorans found throughout East Asia. Our PacBio HiFi reads and Omni-C sequencing data resulted in a high-quality near chromosome-level genome assembly of ∼609 Mb with a scaffold N50 length of 37.34 Mb (96.1% BUSCO). A total of 28,233 genes were predicted, including 28,010 protein-coding genes. The repeat content (27.89%) was similar to the other Chitonidae species and approximately three times lower than in the genome of the Hanleyidae chiton. The genomic resources provided in this work will help to expand our understanding of the evolution of molluscs and the ecological adaptation of chitons.

Chromosome-level genome assembly of the common chiton,Liolophura japonica(Lischke, 1873)