fasciculates with adult labial motor neuron Motor neuron that fasciculates with the labial nerve (Nayak and Singh, 1985). Their cell bodies are found in the subesophageal zone and they innervate muscles of the proboscis (Nayak and Singh, 1985; McKellar et al., 2020). VFB:FBbt_00004042 FBbt:00004042 fly_anatomy.ontology motor neuron proboscis muscle motor neuron labial nerve