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bioRxiv · 10.64898/2026.09.16.752099

Comparative genome analyses suggest a common blueprint for obligate endoparasitism in Strepsiptera

Abstract

The twisted-wing parasites (order Strepsiptera) are well-known for their unusual life histories as obligate endoparasites of a wide variety of other insect orders. Here, we present the first high-quality genome assembly of a leafhopper-parasitizing strepsipteran species. We sequenced the genome of Elenchus koebelei using PacBio HiFi technology, yielding a primary assembly of 63.7Mb in 96 contigs, with an N50 of 1.60Mb and a BUSCO completeness score of 82.3%. In total, we recovered 8,167 protein-coding gene annotations, and 34.2% of the genome annotated as repeats. For the first time, we compare the genome content of three strepsipteran species and find that they are remarkably consistent in broad structure, with approximately 600 insect universal single-copy orthologs that appear to be completely missing from the order. These similarities imply a conserved genomic blueprint for strepsipteran parasitic strategy and/or differences that must be investigated at the post-translational level.

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Millena, R. J. A., Frandsen, P. B., James, M., Tolman, E. R., Uy, F. M.-K., Ware, J. L.. 2026-09-24. Comparative genome analyses suggest a common blueprint for obligate endoparasitism in Strepsiptera. https://doi.org/10.64898/2026.09.16.752099

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