Sicydium, the central american relatively gigantic convergently evolved stiphodon goby.
They're gorgeous, how come we don't see them in the hobby more? I'm assuming it's a similar case to astyanax where they're just hard to ship in spite of there being plenty of them around.
I think there is a degree of demand and popularity, the freshwater gobies already aren’t very popular, and stiphodon must be on higher demand.
Definitely a very nice fish though!