Fig. 6

Comparison of DMNs in WLG1 and WLG3 of the investigated pycnogonids. SLI signal shown in inverted b/w images for better contrast. In order to reveal as many details of the neurites as possible, clipping planes have been applied to Imaris volumes. Dashed lines indicate midline region. Small arrowheads indicate selected longitudinal SL-ir axons within the connectives and passing through the ganglionic neuropil. Note that in case of two labeled PLNs in the shown volume, one soma shows weaker signal intensity. a-c: Walking leg ganglion 3. Each ganglion features two unipolar DMNs per hemiganglion, their respective primary neurite projecting contralaterally (red/light blue asterisks and arrowheads). With the exception of P. litorale (a), one DMN has a smaller soma and more slender neurite. a’-c’: Walking leg ganglion 1. Only one large DMN is present in each hemiganglion (red asterisk and arrowheads). a’ shows an exceptional case, in which a slender ipsilateral projection (arrow) branches off the contralaterally extending primary neurite of a DMN. b’ shows two anterior projections (arrows) send out from the further posteriorly extending contralateral DMN neurite