Did you know that there is a metal scene on Madagascar? In fact, Madagascar, along with Botswana, are among the very few African countries with more or less sizable metal scene, and the history of Malagasy metal can be traced to the late 80s.
Sasamaso isn't a new band as well, being formed in 2002 as the first female-fronted metal band in Madagascar (and probably one of the first in Africa), yet they have next to no physical releases apart from one extremely obscure demo in 2004. Fortunately they now have a Soundcloud page where you can check out some of their tracks. For the most part, their music is based in thrash metal, but I'd say their sound is quite unique and doesn't fit into any particular genre, especially when it comes to tracks like this:
Actually, I can hear a lot of similarities with metal from Malaysia and Indonesia, which is not surprising considering that the first settlers of Madagascar came from that general area and still keep their Austronesian language that's completely unrelated to any of the languages in mainland Africa. Likewise, the metal scene in Indonesia is well developed in comparison to the rest of Asia excluding Japan, much like the Malagasy metal scene in relation to the rest of Africa.
And here's one more track, with a bit more "traditional" metal sound. The quality of recording is far from perfect, but it's totally expected from such an obscure band: