From a marine biologist that studied a specimen I sent her: News of interest! The hard-to-catch shrimp turns out to be Periclimenes iridescens, a poorly known species that has been questionably reported previously from off Panama City. A paper by my colleague Maria Criales of Venezuela indicates that this shrimp tends to associate with sea anemones or other cnidarians. There is some question as to whether this is one species or a species complex, but nobody has enough material of the species to say so. There are fewer than 20 specimens from locations scattered from Cape Hatteras to Venezuela. One of your specimens may be the biggest one ever captured (a whopping inch long). I don't know of any other photos of this shrimp in life but yours. Despite the name "iridescent", Maria Criales noted that her shrimp were translucent, like yours.