While there is a more apparent exhibit for tortoise species in Trader's Alley, this area appears behind an interpretive display about wildlife trafficking.
The reptile department has housed several different tortoise species here, whatever they have that's the appropriate size that year. In the small box in the center of the photo I've seen hatchling Radiated Tortoises, with juveniles in the larger area behind the wooden posts.
It is signed, but not very well, and I didn't even know there were animals here for several months after passing it almost daily. Kind of a nice "surprise" exhibit.