Fig. 3

Serotonin-like immunoreactive nervous system of the lophophore in Crisia eburnea (CLSM). 3D-reconstructions (a-c), volume rendering (d) (different parts of the serotonin-like nervous system shown by different colours), and Z-projections (E-F) of the lophophore after mono-, double, and triple staining for tyrosinated α-tubulin (glow/red), 5-HT (serotonin) (white), and DAPI (blue and green). a 3D-reconstruction combined with volume rendering. General view of serotonin-like immunoreactive nerve elements viewed from the right side. b Nerve elements viewed from the oral side. c Nerve elements viewed from the anal side. d Volume rendering of the lophophore viewed from the anal side. The area of the cerebral ganglion is framed by cyan rectangle. Two latero-distal perikarya are shown by arrowheads. e Serotonin-like perikarya and neurites of the lophophore viewed from the top. f Two oral and one anal large serotonin-like immunoreactive perikarya of the lophophore. Abbreviations: cg - cerebral ganglion; con – circumoral nerve ring; ldl – lophophoral anal nerves; lnp – lower neuropil of the cerebral ganglion; lw – lateral weir of the cerebral ganglion; mo – mouth; mvn – medial visceral nerve; ph – pharynx; sap – anal serotonin-like immunoreactive perikarya; sop – oral serotonin-like immunoreactive perikarya; t – tentacle; unp – upper neuropil of the cerebral ganglion