Fig. 5. The complexity of the nervous system of the polyclad flatworm larva.

(A) HCR staining of cluster markers and neuropeptides (NPs). (B) HCRs with a focus on apical organ neurons and (C) schematic drawing of the Müller’s larva apical organ. All HCR stainings are maximum projections. DAPI, 4′,6-diamidino-2-phenylindole; A, apical view; P, posterior view; V, ventral view; D, dorsal view; L, lateral view with mouth on the left; ee, epidermal eye; ce, cerebral eye. Scale bars, 50 μm.