Fig. 7

Morphology of the tornaria larva of Schizocardium californicum at 36 dpf. Maximum intensity projections of confocal stacks. Larvae are labeled with four markers: phalloidin (green), anti-acetylated tubulin (red) and anti-serotonin (yellow) antibodies, and DAPI (blue) unless otherwise indicated. All panels are anterior to the top and lateral views are ventral to the left. a-c lateral views. b Tubulin channel only, showing organization of the ciliary bands. c DAPI and serotonin channels only, showing the lateral nerve tract passing through the lateral groove and the telotroch nerve tract. d Ventral view, acetylated tubulin and serotonin channels only showing the nerve tract underlying the telotroch. e Close-up ventral view of the pharynx, phalloidin channel only, showing the circular and longitudinal muscles in the anterior and posterior pharynx, respectively. f-i Dorsal views. g DAPI and serotonin channels only, showing the dorsal nerve tract descending along the dorsal midline, and the telotroch nerve tract. h Acetylated tubulin channel only, showing organization of the ciliary bands. i Close-up view of the telotroch, showing the shorter cilia of the secondary telotroch. aa, autofluorescence caused by algal cells in digestive tract; ao, apical organ; as, apical strand; cm, circular pharyngeal muscles; dc, dorsal cluster of the apical organ; ldl, lower dorsal lobe; ll, lateral lobe; lm, longitudinal pharyngeal muscles; ln, lateral nerve tract; ls, lateral saddle; pdl, primary dorsal lobe; pds, primary dorsal saddle; pm, pharyngeal muscles; pof, postoral field; pvl, primary ventral lobe; pvs, primary ventral saddle; st, secondary telotroch; t, telotroch; tn, telotroch nerve tract. vc, ventral cluster of the apical organ. Scale bar: 500 μm (a-d, f-h), 200 μm (e, i)