A chromosome-level genome assembly of tropical purple sea urchin Heliocidaris crassispina

Heliocidaris crassispina is a tropical sea urchin that holds both ecological and economic value and serves as an ideal experimental animal. This study first employed a combination of PacBio HiFi and Hi-C sequencing data to present a high-quality, chromosome-level assembly of H. crassispina genome. This assembled genome spanned 709.77 Mb, with a contig N50 length of 4.98 Mb and a scaffold N50 length of 33.23 Mb. The assembly was anchored on 21 pseudo-chromosomes, covering 98.32% of the genome. A total of 18,665 protein-coding genes were identified, and BUSCO analysis revealed a completeness score of 97.1%. Additionally, non-coding RNAs (ncRNAs) were annotated, including miRNAs, rRNAs, tRNAs and snRNAs, providing a more complete functional understanding of the genome. The high-quality reference genome will enrich the current echinoderm genomic resources and provide a solid foundation for future studies on H. crassispina, including resource surveys, genomic breeding, and marine ranch management.