Nice picture of a nice species. I know it however under the name Mophead iguana and Brown tree climber and had never heared the name Diving lizard ( do they realy dive ? ).
In Europe they are realy rarely kept in public collections but I've seen them regulary at the Oliemeulen in the Netherlands, which was also succesfull in breeding the species.
I think this was the first time I have seen this species. Although they mighty hard to find as they were housed in a very large (tidal) vivarium mixed with Green Anaconda and well camouflaged against the trees trunks/ roots, in the reptile section of the aquarium.