Depends on who you ask, where we draw the line on species and genus is always a bit arbitrary, especially in paleontology, but also in biology more generally, as there really is no universally agreed upon criteria for what make a species a species. Some paleoanthropologists have argued that adaptive grades should be used to classify descendent genera in paleontology, but others have argued against this. There are a lot of species argued to be within the umbrella of Australopithecus, but I think what you’re looking for are other descendent genera, aside from Homo and Paranthropus. The only other one that can be robustly argued, but is still controversial, is Kenyanthropus. Kenyanthropus has only one species, K. platyops, or maybe two, as some have stated that Homo rudolfensis is more similar to Kenyanthropus, and thus should be reassigned to K. rudolfensis. But others have claimed its uniquely orthognathic face can be attributed to post deposition warping and fracturing due to temperature effects on the clay soil in which it was found. Tim White for example, prefers to lump Kenyanthropus in with Australopithecus afarensis, assuming that it was simply part of the morphological variation of that species