Came across these rotten rhizantes flowers during a jungle walk. There were two unopened buds (upper right) which appeared to have been pried open, stepped on or kicked off by something or someone. What a pity. Probably Rhizantes lowii.
I read that there is also a species discovered by the late Prof. Kamaruddin, a noted rafflesia expert in the Lanjak-Entimau area of Sarawak. That species is believed to be a new species.
These are fascinating parasitic plants. Like the Rafflesia, they are only visible when they form buds and flower outside of their hosts. The flowers are much smaller than most rafflesias but are still very beautiful and amazing to look at when fully bloomed.