In order for hardwood suppliers to manage things, they generally lump hardwood types in to groups. For instance, in the oak family, within North America, there are 90 different species, and worldwide 600 different hybrids. Yet for lumber purposes, they are grouped as either white oak, or red oak.
Mahogany isn't quite so diversified, but there are many many different species. The most common seen stuff here is Bif Leaf Mahogan, which grows frrom Mexico all the way down to Brazil. That is very similar stuff to the West African Mahogany as well. As the ultimate in desireablity, there is also the West Indian Mahogany, which is mostly found in the West Indies and Cuba. Really spendy stuff though, like $25+ per bf. You'd better make sure you have a really GOOD reason to buy that stuff rather than the Big Leaf, which is < 1/3 the price.