Live autofluorescence in planulae of Acropora tenuis

Planula larvae of acroporids reveal strong autofluorescence all over the body after treatment with aldehyde fixatives (Fig. 1A), but live planulae of Acropora tenuis show different autofluorescence. Green fluorescence by B-excitation revealed typical bipolar neurons with varicosities along axons (Fig. 1B), even though these neurons were only seen in small numbers of planulae, and only sparsely. In contrast, red fluorescence by G-excitation revealed numerous rod-like structures dotted in the ectodermal layer over the whole body (Fig. 1C-E) of all planulae so far observed (more than 30 individuals). These signals resemble the cell body of neurons visualized by immunohistochemistry targeting a neuropeptide Live autofluorescence in planulae of Acropora tenuis