Documentation

Electron Microscopy Data

Electron Microscopy Data available on Virtual Fly Brain.

Virtual Fly Brain brings together data from multiple electron microscopy (EM) resources, providing access to high-resolution neuroanatomical datasets. These datasets include complete EM volumes of Drosophila brains and ventral nerve cords, neuron reconstructions, connectivity information and neurotransmitter predictions. Data can be visualised using the web browser or accessed programmatically via APIs.

488,111
neurons with connectivity
34.7 M
synaptic connections
14,363
cell types with neuron images

The synaptic connectivity derived from these datasets is described on its own page. See Connectivity data for what an edge means, which connectomes contribute one, and how to handle reconstructions that cover the same tissue.

Comparison Table of Integrated Datasets

The table below summarises EM datasets that have been integrated into VFB, including the portion of the organism covered (Anatomy), the resource(s) where the original data can be found, The level of reconstruction (sparse or dense) and the original publication for the dataset.

DatasetVFB symbolVersion in VFBAnatomyReconstructionResource(s)Original Publication
BANCBANCv626Full CNS (adult female)DenseCodexBates et al. (2025), published as Bates et al. (2026)
male-CNSmcv0.9Full CNS (adult male)DenseNeuPrint; CodexBerg et al. (2025)
Optic-lobeolv1.0.1Optic lobe (adult male)DenseNeuPrint; CodexNern et al. (2025)
FAFB (FlyWire)fwv783Full brain (adult female)DenseCodexDorkenwald et al. (2024); Schlegel et al. (2024)
MANCmvv1.2.1Full VNC (adult male)DenseNeuPrint; CodexTakemura et al. (2024)
Hemibrainhbv1.2.1Partial brain (adult female)DenseNeuPrintScheffer et al. (2020)
FAFB (CATMAID)fafbFull brain (adult female)SparseCATMAIDZheng et al. (2018)
L1 CNS (CATMAID)l1emFull CNS (female larva)SparseCATMAIDOhyama et al. (2015)
FANCFull VNS (adult female)SparseCATMAIDPhelps et al. (2021)

A neuron count, and often a neuron’s identifier, is a property of a release rather than of a dataset. The versions above are what VFB currently holds; see Connectome versioning for what changes between releases and how to follow an identifier across them. The same version list, with the symbols used to include or exclude a dataset from a query, is on the Connectivity data page.

FlyWire, hemibrain and FAFB (CATMAID) are reconstructions of the same tissue. Counting across them double-counts neurons; Connectivity data explains how VFB handles that and which datasets to exclude.

Datasets Hosted by VFB

Virtual Fly Brain (VFB) hosts several CATMAID instances for exploring connectomic reconstruction data. These datasets provide access to neuroanatomical data from various Drosophila electron microscopy projects. Each instance has its own page under sites hosted by VFB.