de novo Assembly of five Highly Contiguous Heliconius Butterfly Genomes With Long-Read Sequencing Alone

Rapidly decreasing costs of sequencing whole genomes have caused a boom in genomic resources for many species. However, many key nonmodel systems that were sequenced early in the genomic revolution lack assemblies that reflect the quality and contiguity that are routine with current technology. Some of these "early for assembly, late for contiguity" genomes belong to the butterfly genus Heliconius, a remarkably fruitful clade for exploring questions of phenotypic mimicry, speciation dynamics, and population genetics. We de novo assembled five new reference genomes of Heliconius butterflies based on PacBio HiFi sequencing: two subspecies of H. erato, two subspecies of H. melpomene, and a closely related species, H. numata. While independent assemblies of multiple subspecies are already a valuable resource, these specific genomes are important for exploration of the genomic basis of mimicry, because the four H. erato and H. melpomene genomes represent two pairs of H. erato/H. melpomene local comimics. These genomes prove to be high quality (merqury quality score 51 to 58) and approach completeness (>98% BUSCO complete genes) over a lower number of longer contigs than earlier Heliconius genomes, illustrating how PacBio long-read technology alone can unlock untapped genomic resources. This set of high-quality, uniformly processed genomes represents an important resource for exploring the genomics of adaptation, hybridization, and speciation.