Technically, they are not different - assuming the listing is correct (that is, they are not hybrids or a different species - quite a lot of fish called
are
)
Well, there are two different aspects of this:
1. Size - LARGE should mean a fair bit bigger than small - and these fish don't grow very quickly.
2. Wild-caught is (assuming it's correct) a guarantee that it's not a hybrid, at the very least, and for breeding purposes, they are not closely related [most likely].
--
Mats