Fig. 5

Immunocytochemistry in pediveliger larvae of Nodipecten nodosus. Lateral view (anterior to the top, ventral to the right). Staining with anti-serotonin (a–b) and phalloidin (c–d), as revealed by confocal laser scanning microscopy (CLSM). a Pediveliger showing strong serotonin-like immunoreactivity (yellow) in the central and peripheral nervous system, particularly in the circumpallial nerve (arrows) and the pedal nervous plexus. Nuclei are stained in blue by DAPI. b 3D reconstruction of the pediveliger nervous system based on a CLSM image stack showing the mantle innervation in detail. Arrow points to the developing cerebral ganglia and arrowhead to the visceral ganglion. c Larval musculature of the right half of an individual. d 3D reconstruction of the pallial musculature, showing retractor and margin-parallel muscles; arrows point to striated fibers and arrowheads to suggested non-striated fibers. Abbreviations: aa, anterior adductor; cp, circumpallial nerve; fo, foot; mm, mantle margin; mp, margin-parallel muscles; pa, posterior adductor; pn, pallial nerves; rm, retractor muscles; ve, larval velum