Abstract
Nematodes such as Caenorhabditis elegans and Pristionchus pacificus are powerful models for associating phenotypes to genotypes. However, exploring the evolution of identified genetic loci requires a robust phylogenomic framework. Here, we present an updated genome of the nematode Parapristionchus giblindavisi which is the only known member of the sister group of Pristionchus. Reassembly of previously generated long read sequencing data combined with new Hi-C data resulted in a near chromosome-scale genome assembly spanning 302.5Mb. The Hi-C contact map, karyotyping data and comparative genomic analysis support an organization of the P. giblindavisi genome into six chromosomes, whereby all autosomes correspond to individual Nigon elements and the sex chromosome represents a fusion of Nigon elements D and X. The further improved P. giblindavisi genome will be useful as an outgroup for dating and polarizing lineage-specific genomic signatures.