Benthigem
Taking advantage of the abundant marine snow and lack of any competition, some deep sea species of sea rupees have found their way down the sea floor into the deeper depths of the ocean. The benthigems have lost their mixotrphic abilities entirely, relying solely on the organic matter that sinks to the sea floor. Life on the sea floor is harsh and slow going, and as such these crystal flora have had to specialize. Their internal mycosal cores are smaller then their ancestors, however their chitin layers have grown thick to deal with the crushing pressure. They are able to go somewhat dormant in times of scarcity, and can live long lives growing slowly, but when the decomposing bodies of larger organisms float down to the surface they rapidly attempt to multiply and release spores, which will then free float along the current until they find a suitable surface to connect. Pathogens rarely find their way to them, but when they do they have to not only contend with their thick chitin layers, but they well adapted immune system inherited from their ancestors.