this was the only exhibit that wasn't signed in the amphibian conservation center. It's definitely a species I have seen before but I just can't recall its name.
@SwampyT. venustus was my initial guess aswell, but I couldn't find a photo that matched the individuals color well, I know Dallas has this species and Fort Worth did so I compared with those photos, and while not exactly the same, the fort worth individual was more brown, that the typical green like the one at Dallas, so I think it is likely this is a darker morph of the Beautiful Pit-Viper(T. venustus)