Figure 12

Brain and muscle development of P. dumerilii , 32-38 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 branch of the circumesophageal connectives (drcc and vrcc) become thicker and the prototroch ring nerve (ptrn) is well visible. The dorsal and ventral roots of the circumesophageal connectives connect the cerebral commissures (cc). B, G, L, Q: Additionally to the first and second serotonergic cell (white star and white arrow respectively) two more serotonergic cells develop laterally in the brain of the larvae (white arrows). C, D, H, I, M, N, R, S: The dorsal longitudinal muscles (dlm) become more pronounced. The ventral longitudinal muscles (vlm) become clearly visible around 32 hpf. E, J, O, T: The amount of cells on the ventral side of the episphere is increasing. CLSM microscopy, maximum projection, Imaris surpass mode. Scale bar in all images 20 μm. Further abbreviations see abbreviations list.