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bioRxiv · 10.64898/2026.11.10.765633

A chromosome-level genome assembly of the endangered northern dragonhead sap beetle, Thymogethes norvegicus (Easton, 1959)

Strand, M. A.·Toerresen, O. K.·Skage, M.·Ferrari, G.·Tooming-Klunderud, A.·Elven, H.·Jakobsen, K. S.
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Abstract

The northern dragonhead sap beetle (Thymogethes norvegicus) is believed to be endemic to Norway and is classified as endangered. Its life cycle is closely tied to the host plant northern dragonhead (Dracocephalum ruyschiana), itself classified as vulnerable in Norway. Here, we present a chromosome-level genome assembly of a male T. norvegicus. The assembly comprises two pseudo-haplotypes, hap1 and hap2, of 1,142 and 1,109 Mb, with 96.3% and 96.8% scaffolded into chromosomes, respectively. Hap1 contains 8 autosomes and the X chromosome, while hap2 contains 8 autosomes. Assembly quality was high, with conserved single-copy ortholog completeness scores of 96.6% and 90.7% and combined k-mer completeness of 98.1%. A total of 13,484 and 12,550 protein-coding genes were annotated in hap1 and hap2, respectively. This assembly provides a valuable genomic resource for the conservation of this endangered endemic species totally dependent on the vulnerable plant, the northern dragonhead.

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Strand, M. A., Toerresen, O. K., Skage, M., Ferrari, G., Tooming-Klunderud, A., Elven, H., Jakobsen, K. S.. 2026-11-11. A chromosome-level genome assembly of the endangered northern dragonhead sap beetle, Thymogethes norvegicus (Easton, 1959). https://doi.org/10.64898/2026.11.10.765633

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