A chromosome-level reference genome assembly of the King Ratsnake (Elaphe carinata)

The King Ratsnake (Elaphe carinata), a widely distributed non-colubrine snake in East Asia, exhibits a remarkable capacity for broad-spectrum venom resistance, enabling it to prey on other snakes, including lethal viperid and elapid species. Despite its ecological and physiological significance, the genetic basis of this trait remains largely unknown. Here, we present a chromosome-level genome assembly of E. carinata, generated using PacBio HiFi long-read sequencing, Illumina short-read data, and RNA-seq-supported by a synteny-based scaffolding approach using the closely related Elaphe schrenckii. The 1.62 Gb assembly (contig N50 = 2.77 Mb, scaffold N50 = 143.07 Mb) achieves 97.3% BUSCO completeness, with over 90% of sequences anchored into 18 pseudochromosomes. Repetitive sequences account for 53.19% of the genome, with LINE elements being the most abundant. We annotated 19,750 protein-coding genes, of which 99.2% were functionally assigned using integrated evidence from homology, transcriptomics, and ab initio predictions. This high-quality genomic resource provides a foundation for exploring colubrid evolution, venom resistance mechanisms, and the development of novel antivenom therapies.