Exotic Mahogany is a tonewood used exclusively by Kala. What makes it "exotic" isn't exactly something Kala has specified. Broadly, Mahogany is endemic to the Americas so, from a outdated Old World New World perspective, the wood would be considered "exotic". The experts here at UkuleleMate cannot comment too much more on this, but we can tell you about the physical and tonal characteristics of the wood.
Physically, Exotic Mahogany is much lighter than Mahogany. It is closer to an Oak or even a Spruce. It has a subtle grain and rippling, again like Oak. It certainly pairs well with the darker hues of Rosewood and Ebony, which are favoured for fretboards and bridges.
Tonally, it is definitely related to Mahogany, but a touch more mellow. Customers who are tossing up between the two, often go for the Exotic Mahogany because of this. It feels a little more complex, perhaps a little bassier and woodier. As a result, this tonewood tends to be 50-100 AUD more expensive than its Mahogany counterparts.