A new connectome of the right optic lobe from a male Drosophila central nervous system and a comprehensive inventory of the fly's visual neurons are reported. A computational framework was developed to quantify the anatomy of visual neurons, establishing a basis for interpreting how their shapes relate to spatial vision. By integrating this analysis with connectivity information, neurotransmitter identity, and expert curation, ~53,000 neurons were classified into 727 types, about half of which are systematically described and named for the first time. An extensive collection of split-GAL4 lines matched to the neuron type catalog is shared. This comprehensive set of tools and data unlock new possibilities for systematic investigations of vision in Drosophila, a foundation for a deeper understanding of sensory processing. The fly visual system comprises several distinct anatomical regions: the lamina, medulla, accessory medulla, lobula, and lobula plate, forming the structure called the optic lobe. These regions are referred to as neuropils, structures dense with the synaptic connections of dendrites and axons. The neurons of the Drosophila visual system were classified into three main groups: Optic Lobe Intrinsic Neurons (OLINs), Optic Lobe Connecting Neurons (OLCNs), and Visual Projection Neurons (VPNs) and Visual Centrifugal Neurons (VCNs). The connectome contains ~49 million connections in the visual brain regions. The number of connected cells in the network spans five orders of magnitude across the visual cell types. The study also identified neurotransmitters used by each neuron type to communicate across synapses. A neural network was trained to classify synapses into one of seven transmitters (acetylcholine, glutamate, GABA, histamine, dopamine, octopamine, and serotonin) using the known transmitters of 59 cell types. The prediction accuracy was further improved when the single-synapse predictions were aggregated across the cells of each type. The results show that most neurons appear to release the same neurotransmitter(s) across their various terminals, and molecular profiling suggests that most neurons signal with a single dominant neurotransmitter. The study also identified specialized cell types, such as the Dorsal Rim Area (DRA) neurons, which are specialized for detecting polarized light. The Accessory Medulla is a small brain region with a well-established role in clock circuitry and circadian behaviors. The study also identified the Visual Projection Neurons (VPNs) and Visual Centrifugal Neurons (VCNs), which are the final group of neurons presented as a complete set. The study also developed cell-type-specific genetic driver lines that can be used to manipulate or mark specific cell types for functional imaging or electrophysiology. The study also examined the inter-region connectivity of the fly brain, revealing that the flow of visual information is substantial. The study also identified the central brain regions that receive significant, directA new connectome of the right optic lobe from a male Drosophila central nervous system and a comprehensive inventory of the fly's visual neurons are reported. A computational framework was developed to quantify the anatomy of visual neurons, establishing a basis for interpreting how their shapes relate to spatial vision. By integrating this analysis with connectivity information, neurotransmitter identity, and expert curation, ~53,000 neurons were classified into 727 types, about half of which are systematically described and named for the first time. An extensive collection of split-GAL4 lines matched to the neuron type catalog is shared. This comprehensive set of tools and data unlock new possibilities for systematic investigations of vision in Drosophila, a foundation for a deeper understanding of sensory processing. The fly visual system comprises several distinct anatomical regions: the lamina, medulla, accessory medulla, lobula, and lobula plate, forming the structure called the optic lobe. These regions are referred to as neuropils, structures dense with the synaptic connections of dendrites and axons. The neurons of the Drosophila visual system were classified into three main groups: Optic Lobe Intrinsic Neurons (OLINs), Optic Lobe Connecting Neurons (OLCNs), and Visual Projection Neurons (VPNs) and Visual Centrifugal Neurons (VCNs). The connectome contains ~49 million connections in the visual brain regions. The number of connected cells in the network spans five orders of magnitude across the visual cell types. The study also identified neurotransmitters used by each neuron type to communicate across synapses. A neural network was trained to classify synapses into one of seven transmitters (acetylcholine, glutamate, GABA, histamine, dopamine, octopamine, and serotonin) using the known transmitters of 59 cell types. The prediction accuracy was further improved when the single-synapse predictions were aggregated across the cells of each type. The results show that most neurons appear to release the same neurotransmitter(s) across their various terminals, and molecular profiling suggests that most neurons signal with a single dominant neurotransmitter. The study also identified specialized cell types, such as the Dorsal Rim Area (DRA) neurons, which are specialized for detecting polarized light. The Accessory Medulla is a small brain region with a well-established role in clock circuitry and circadian behaviors. The study also identified the Visual Projection Neurons (VPNs) and Visual Centrifugal Neurons (VCNs), which are the final group of neurons presented as a complete set. The study also developed cell-type-specific genetic driver lines that can be used to manipulate or mark specific cell types for functional imaging or electrophysiology. The study also examined the inter-region connectivity of the fly brain, revealing that the flow of visual information is substantial. The study also identified the central brain regions that receive significant, direct