etan: Do you have a photo of the entire plant? I've personally never seen a
Thaumatophyllum spruceanum but the stems (what I can see of them from your photo) look alive and healthy. I'm not sure what you mean when you say the cataphyll on your plant is empty? Could it be that the once the leaf emerged the cataphyll dried up and fell off? That would be normal with some philodendrons. Hopefully someone more familiar with this particular Philo will pop in with some advice.
karmatree: Here ya go, I copied and pasted this from Wikipedia:
"Philodendrons also produce cataphylls, which are modified leaves that surround and protect the newly forming leaves. Cataphylls are usually green, leaf-like, and rigid while they are protecting the leaf. In some species, they can even be rather succulent. Once the leaf has been fully formed, the cataphyll usually remains attached where the stem and base of the leaf meet. In philodendrons, cataphylls typically fall into two categories: deciduous and persistent types.[14] A deciduous cataphyll curls away from the leaf once it has formed, eventually turning brown and drying out, and finally falling off the plant, leaving a scar on the stem where it was attached. Deciduous cataphylls are typically found on vining philodendrons, whereas persistent cataphylls are typical of epiphytic philodendrons or appressed climbers. In the latter, the cataphylls are prevented from falling off in a timely manner due to the short internodes of the plant. The cataphylls will remain attached, drying out and becoming nothing more than fibers attached at the nodes. In some philodendrons, the cataphylls build up over time and eventually form a wet mass at the nodes. This may keep emerging roots moist and provide some form of lubrication to new leaves."
