The leaves don't split because the plant is old. They split because it finally believes it's climbing a tree.
The plant the genus is built around, ranging across Southeast Asia and the Pacific. Juvenile leaves are narrow, glossy, and undivided; mature foliage on a thick post becomes deeply pinnate with elliptical fenestrations along the midrib. Give it a 6-inch wide moss or cork pole and it will rewrite itself within two years. Don't confuse it with Rhaphidophora decursiva, which it superficially resembles but is unrelated.
The referenceThe rest of this story is for subscribers. One Leaf People subscription unlocks every Understory feature and Field Guide — in the app and here on the web.
The Field Guide from Leaf People.