The female larval fly CNS connectome: first draft

Mohinta, S.; Franco-Barranco, D.; Lee, S. Y.; Gomez-Galvez, P.; Agrawal, S.; Clayton, M.; Barnes, C. L.; Randel, N.; Correia, A.; Ceffa, N.; Velichkova, N. S.; Nielsen, K.; Hess, H.; Pang, S.; Xu, C. S.; Berni, J.; Januszewski, M.; Zlatic, M.; Cardona, A.

doi:10.64898/2026.09.28.754924

bioRxiv · 10.64898/2026.09.28.754924

The female larval fly CNS connectome: first draft

Mohinta, S.·Franco-Barranco, D.·Lee, S. Y.·Gomez-Galvez, P.·Agrawal, S.·Clayton, M.·Barnes, C. L.·Randel, N.·Correia, A.·Ceffa, N.·Velichkova, N. S.·Nielsen, K.·Hess, H.·Pang, S.·Xu, C. S.·Berni, J.·Januszewski, M.·Zlatic, M.·Cardona, A.

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Abstract

We release an enhanced FIB-SEM volume and associated neuron, mitochondria, synapse and glia automated segmentations for the complete, gap- and artifact-free central nervous system of the first instar female larval Drosophila melanogaster. Segmentation data is largely unproofread besides select neurons in the premotor and proprioceptive system and select subvolumes where synapses have been manually annotated, serving as training and evaluation data. The dataset represents the first complete central nervous system of the larval fly, and now awaits substantial improvement of machine vision approaches that effectively leverage domain knowledge for the automated yet data-guided proofreading, or substantial and costly human proofreading. All the data and methods are publicly available for further improvement and analysis.

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Mohinta, S., Franco-Barranco, D., Lee, S. Y., Gomez-Galvez, P., Agrawal, S., Clayton, M., Barnes, C. L., Randel, N., Correia, A., Ceffa, N., Velichkova, N. S., Nielsen, K., Hess, H., Pang, S., Xu, C. S., Berni, J., Januszewski, M., Zlatic, M., Cardona, A.. 2026-10-07. The female larval fly CNS connectome: first draft. https://doi.org/10.64898/2026.09.28.754924

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