Fig. 8

Nervous system of Pycnophyes kielensis stained with antibodies against serotonin, α-, and β-tubulin. Maximum projection micrographs obtained with a confocal laser scanning microscope. The nervous system was stained with primary antibodies against serotonin, α-, and β tubulin. Tubulin appears white-orange, serotonin appears pink. Cell nuclei where stained with DAPI and appear blue together with autofluorescence of the cuticle. a Overview of the nervous system stained by tubulin and serotonin in the anterior part of P. kielensis showing the neuropil ring, pharyngeal bulb nerve cords, and the ganglion in segment six behind the pharyngeal bulb. b Overview of the nervous system stained by tubulin and serotonin in the posterior of P. kielensis with ganglion in segment six, merged ventral nerve cords, and lateral nerve cords in the posterior segments. Note the punctate immunoreactivity is not neuro-specific but most probably the staining of sperm cells that have a microtubule containing tail (axoneme). c 3D reconstruction of b. ga ganglion, lan lateral nerve cord, np neuropil, pbn pharyngeal bulb nerve cord, so somata, vnc ventral nerve cord