Figure 16

Brain and muscle development of P. dumerilii , 48-54 hpf, apical view, dorsal side up. The age of the larvae in each row is given in the lower left corner of the first picture of each row. The displayed staining is indicated at the bottom of each column. A, F, K, P: The dorsal and ventral branches of the circumesophageal connectives (drcc and vrcc) approach each other. The distance between the prototroch ring nerve (ptrn) and the prototroch (pt) begins to increase and the prototroch ring nerve approaches the cerebral commissures (cc) (e.g. compare A, F, K and P). B, G, L, Q: Four serotonergic cells are visible in the brain (the central one marked with a white star, the more dorsal ones marked with white arrows). C, D, H, I, M, N, R, S: The dorsal longitudinal muscles (dlm) and ventral longitudinal muscles (vlm) are intensely stained. E, J, O, T: The stomodeum is well visible in the episphere. CLSM microscopy, maximum projection, Imaris surpass mode. Scale bar in all images 20 μm. Further abbreviations see abbreviations list.