Abstract
The mosquito, Culex tarsalis, is a key vector species in the western United States due to its role in transmission of zoonotic arboviruses that affect human health. Extensive research has been conducted on Cx. tarsalis ecology, feeding behavior, vector competence, autogeny, diapause, genetics, and insecticide resistance. However, the lack of a published reference genome has limited genomic analyses for this species, although a previous population genetic analysis of microsatellite allele frequencies across the western U.S. identified three geographic clusters. Salivary gland-specific gene expression has also revealed genes involved in blood feeding. To facilitate genomic studies in this important vector species, we have assembled and annotated a reference genome (CtarK1) based on PacBio HiFi reads from a single male and 10X linked-reads. Genome completeness was 71.5% based on the Benchmarking Universal Single-Copy Orthologs (BUSCO) tool and the N50 was 59 kb. The largest contig was 5.7Mb, including 678kb of unknown bases. CtarK1 is 37% larger than Cx. quinquefasciatus (800Mb vs. 579Mb); a difference that is largely transposable elements. Using the Cx. tarsalis transcriptome and protein sequences from Culex quinquefasciatus, 15,682 genes were annotated in the CtarK1 genome. Based on full mitochondrial genome alignments we present a Bayesian phylogeny and estimate the divergence time from Culex quinquefasciatus at 13 MYA (+/− 4).