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bioRxiv · 10.64898/2026.05.27.728183

ERGA-BGE reference genomes of Hyalomma lusitanicum and its obligate Francisella endosymbiont as a genomic resource for One Health research

Abstract

Hyalomma lusitanicum is a characteristic tick species of the western Mediterranean region, with a well-established distribution across the Iberian Peninsula. It is strongly associated with wild ungulates, particularly red deer, as well as livestock, to which it can transmit a wide range of pathogens, including viruses, bacteria, and protozoa. Here, we present three genomic resources for H. lusitanicum: a scaffold-scale nuclear genome, the complete mitochondrial genome, and the complete genome of its associated Francisella bacterial endosymbiont. The nuclear genome assembly spans 1.81 Gb and comprises 59 scaffolds, with a scaffold N50 of 153.6 Mb (L50 = 5) and no gaps, indicating high contiguity and completeness with a gene annotation completeness BUSCO score of 97.1 %. Genome annotation of the nuclear assembly identified 20,638 protein-coding genes, 1,422 non-coding genes, and 5,775 pseudogenes. A total of 18 scaffolds were assembled as putative chromosomes, exceeding the 11 chromosomes inferred as ancestral; however, synteny analyses suggest that several scaffolds likely represent fragmented portions of the same chromosome, probably due to incomplete Hi-C scaffolding. Despite this, the assembly represents one of the most complete tick nuclear genomes generated to date. In addition, we report the complete genome of a Francisella endosymbiont (1.51 Mb, 1,679 genes), characterized by a high proportion of pseudogenes and reduced genome size, consistent with patterns of genome reduction associated with obligate symbiosis. Together, these genomic resources provide a framework to investigate local adaptation and host-symbiont evolution, and to support improved surveillance, control, and management strategies for species of public health relevance.

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BibTeXRIS

Uribe, J. E., Echeverry-Perez, J. S., Valcarcel, F., Olmeda, A. S., Sanchez-Sanchez, M., Tercero, J. M., Escudero, N., Fernandez, R., Boehne, A., Monteiro, R., Gut, M., Aguilera, L., Camara Ferreira, F., Cruz, F., Gomez-Garrido, J., Alioto, T., de Guttry, C.. 2026-05-31. ERGA-BGE reference genomes of Hyalomma lusitanicum and its obligate Francisella endosymbiont as a genomic resource for One Health research. https://doi.org/10.64898/2026.05.27.728183

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