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bioRxiv · 10.1101/2025.10.31.685973

Chromosome-scale genome assembly and annotation of the two-spotted cricket Gryllus bimaculatus (Orthoptera: Gryllidae)

Kataoka, K.·Sanno, R.·Gaczorek, T.·Bhattarai, U. R.·Ito, Y.·Inoue, S.·Yura, K.·Asahi, T.·Ylla, G.·Mito, T.·Extavour, C. G.
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Abstract

The two-spotted cricket, Gryllus bimaculatus, is a key hemimetabolous model organism for developmental biology, neuroscience, and regeneration. The existing reference genome is, however, highly fragmented into 47,877 scaffolds, hampering chromosome-scale analyses for these fields. Here, we report a high-quality, chromosome-scale genome assembly for the white-eyed mutant strain of this cricket, generated using a combination of Nanopore and PacBio HiFi long reads, integrated with Hi-C data. The final 1.62 Gbp assembly achieves a scaffold N50 of 107.4 Mbp, a significant improvement in contiguity over the previous 6.3 Mbp N50. We anchored 94.45% of the assembly into 15 pseudomolecules, consistent with the known karyotype (n = 15). The genome completeness (BUSCO v6.0.0 insecta_odb12) reached 98.1%. We also updated the annotation, identifying 14,964 protein-coding genes. This gene set shows markedly improved completeness (BUSCO v6.0.0 insecta_odb12: 95.7%) compared with the previous annotation (81.2%) and successfully recovers all nine essential neuropeptide genes previously reported as missing from the draft assembly. This chromosome-scale genomic resource provides an essential foundation for comparative and functional genomics in G. bimaculatus.

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Kataoka, K., Sanno, R., Gaczorek, T., Bhattarai, U. R., Ito, Y., Inoue, S., Yura, K., Asahi, T., Ylla, G., Mito, T., Extavour, C. G.. 2025-11-03. Chromosome-scale genome assembly and annotation of the two-spotted cricket Gryllus bimaculatus (Orthoptera: Gryllidae). https://doi.org/10.1101/2025.10.31.685973

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