part of develops from VUM precursor larval VUM neuron FBbt:00001592 VUM-cluster neurons ventral unpaired median neuron VFB:FBbt_00001592 The cell body of the VUM neuron is located medially in the ventral and posterior cortex region of the neuromere. Fibers from VUM neurons run tightly fasciculated dorsally towards the neuropil where they separate to form a motorneuronal projection bifurcating in the dorsal part of the anterior commissure, and an interneuronal projection bifurcating in the ventral part of the posterior commissure (Bossing and Technau, 1994). There are usually six VUM neurons per neuromere in the late embryo and larva. ventral unpaired cell fly_anatomy.ontology larva neuron larval ventral midline neuron