Fig. 11

Magelona mirabilis, immunohistochemical patterns in larval stages. Confocal z-projections and volume renderings (c (inset), d, e, g). DNA staining with DAPI is shown in blue. Apical is up in all images except of (e) and (f) which show an apical view. Stages are given in days post fertilization (dpf). a: The nervous system of larvae around 5 dpf is characterized by the presence of well-developed neurites along the larval palp (pa) and along the ventral nerve cord (vn). The inset shows distinct circumesophageal connectives (cc) and a separate esophageal nerve ring (er). b: 5-HT-lir reveals the presence of a prominent apical soma (white arrowhead) and at least two neurite bundles forming the ventral nerve cord (vn). 5-HT-lir is present in the dorsal root of the circumesophageal connective (dr). c: FMRFamide-LIR is present in the apical organ (ao), the circumesophageal connectives (cc), in the esophageal nerve ring (er) and in the ventral nerve cord (vn). The inset shows a volume-rendering of the FMRF-lir in the apical region. d: The apical organ (ao) at 9 dpf is more developed than in the previous stages. A volume-rendering reveals the presence of at least five distinct somata showing FMRFamide-lir. e: The latter somata are located sagital and ventral of the circumesophageal connective (cc). f: An apical view of the anterior end at 13 dpf shows the dorsal (dr) and ventral root (vr) with outgoing palp nerves (pn) and distinct interconnections (red arrowheads, red dotted line). g: 5-HT-lir in the same stage reveals a prominent staining of the (dr) and the (er). The (vr) is only scarcely stained. mo, mouth opening; ne, nephridia; The scale bars only refer to the main images, not to the inserts