In the many years I lived in Fl and kept potted trees and bonsai, many of the more northern temperate species I saw that somehow made their way to Florida looked similarly (there weren't many, but a high percentage of the ones I did see). I think this due to a combination of factors related to the trees being kept in a generally unsuitable unsuitable climate for longterm health and vigor(the most important of which being lack of chilling hours for proper dormancy).
From what I have read, generally speaking, trees that require winter cold can survive roughly 2 years after the last proper dormant period before finally succombing when there is a complete lack of any winter chilling hours given. If this tree was located in the Northern (or cooler parts of Central Fl) and/or was only there for a short time, the above 2 year rule of thumb may not apply.
I would say, give it excellent care relative to its species going forward and hope for the best.
I agree with Les re what a convincing root-over-rock specimen you have there.