To evaluate the completeness of the assembly and the uniformity of the sequencing, all the paired-end reads were mapped to the assembly using BWA33. The mapping rate was 98.51% and the genome coverage was 99.84%. This result suggested that our assembly results contained almost all the information in the reads (Supplementary Table 3). Gene region completeness was evaluated from the scape tissue, of 80,646 transcripts assembled by Trinity34, 98.66% could be mapped to our genome assembly, and 94.41% were considered as complete (more than 90% of the transcript could be aligned to one continuous scaffold). CEGMA35 (Core Eukaryotic Genes Mapping Approach) defined a set of conserved protein families that occur in a wide range of eukaryotes, and identified their exon–intron structures in a novel genomic sequence. Through mapping to the 248 core eukaryotic genes, a total of 239 genes with a ratio of 96.37% were found in G. elata (Supplementary Tables 5). Genome completeness was also assessed using BUSCO gene set analysis version 2.013 which includes a set of 956 single-copy orthologous genes specific to Plantae.