Nepenthes rajah, Another Species Dependent Upon Mammal Droppings

Following my previous posts about N. bicalcarata, N. hemsleyana, and N. lowii, I discovered that another species of Nepenthes, Nepenthes rajah, also secures a large part of its nitrogen content from animal droppings, specifically, the droppings of the Mountain Treeshrew, Tupaia montana, like N. lowii, as well as the Summit Rat, Rattus baluensis. N. rajah is unique among Nepenthes, as far as is currently known to science, in having mutual relations with two mammalian species, one of which, the Mountain Treeshrew, is active during the day, and one of which, the Summit Rat, is active during the night. As a consequence of this division of activity, droppings are largely received from the Mountain Treeshrew during the day, while droppings from the Summit Rat are largely received during the night. See the graph below:

White Bars = Mountain Tree Shrew; Black Bars = Summit Rat

Interestingly, when compared to N. lowii and N. macrophylla, both of which have a mutual relationship with the Mountain Treeshrew, N. rajah's lower lid surface is most visually noticeable for the Mountain Treeshrew, indicating that, evolutionarily, it has long depended upon the Mountain Treeshrew for supplemental nutrition.

N. rajah is a very endangered species, occurring only in a few isolated spots within Kinabalu National Park, as shown above. These rare occurrences correspond with the presence of serpentine soils containing high concentrations of nickel and chromium. Further, being an upper highland plant, it often sees temperatures fall to near freezing, as well as intense rain patterns, resulting in slow growth. 

In cultivation, no grower, to my knowledge, appears to have attempted to replicate the serpentine soils of N. rajah's homeland, most preferring to use a typical Nepenthes media mixture involving long-fibered sphagnum peat moss and some mix of sand, perlite, vermiculite, or orchid bark. Still, N. rajah is known to be an exceptionally slow grower, even in these more "ideal" conditions, though I would like to see if a change in media composition could speed up the growth process.