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bioRxiv · 10.1101/2025.03.14.643333

Chromosome-level genome assembly and annotation of the chaetognath Flaccisagitta enflata

Guiglielmoni, N.·Eitel, M.·Moreau, P.·Krebs, S.·Vermeij, M.·Koszul, R.·Flot, J.-F.
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Abstract

Chaetognaths, a phylum of enigmatic marine predators, present a significant challenge to phylogenetic reconstruction due to their uncertain evolutionary placement. While transcriptome analyses have suggested affinities with the Gnathifera clade, genomic data for this group remain scarce, hindering a comprehensive understanding of their evolution. Here, we present the first chromosome-level genome assembly of Flaccisagitta enflata, a species within the Aphragmophora order. The genome assembly includes 9 chromosome candidates with a total size of 794 Mb and a BUSCO score of 91.3% against the Metazoa lineage. This high-quality genome assembly provides a crucial resource for comparative genomic analyses within Chaetognatha and the broader Gnathifera clade, and it will facilitate investigations into chaetognath evolution and their phylogenetic relationships, addressing long-standing questions regarding their placement within the animal kingdom.

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Guiglielmoni, N., Eitel, M., Moreau, P., Krebs, S., Vermeij, M., Koszul, R., Flot, J.-F.. 2025-03-17. Chromosome-level genome assembly and annotation of the chaetognath Flaccisagitta enflata. https://doi.org/10.1101/2025.03.14.643333

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