A high-quality chromosome-level genome assembly and annotation of the medicinal orchid Cremastra appendiculata (Orchidaceae).

Abstract

Cremastra appendiculata (D. Don) Makino, an endangered terrestrial orchid with significant medicinal value, lacks comprehensive genomic resources to elucidate its evolution and conservation genetics. Here, we present a chromosome-level genome assembly for C. appendiculata, generated by integrating PacBio circular consensus sequencing and Hi-C technologies. The final genome assembly totals 2.40 Gb, achieving contig and scaffold N50 values of 27.47 Mb and 98.06 Mb, respectively. Hi-C scaffolding anchored 98.66% of the assembly to 24 chromosomes, with repetitive elements comprising 83.85% of the genome and a total of 31,703 protein-coding genes predicted, of which 29,094 (91.77%) were functionally annotated. This high-quality, chromosome-level reference genome provides a foundational resource for understanding the population genetic structure, adaptive evolution and speciation mechanisms of C. appendiculata, thereby offering valuable insights into its evolutionary history and conservation.