Sorry to you both that I didn't reply to your comments - of some reason the function for following the topic was switched off... :-(
I must admit that I really struggle in differentiating the species of Gobies, e.g. P. micheli and P. mossambica.
Is it absolutely impossible that P. mossambica lives on a hard coral?
If so, is P. micheli the only alternative?
Thanks so far!