Eduardo Goncalve's message on his visit to the Burle-Marx collection (the
lucky devil!) jogged my somewhat uncertain memory about Philodendron
spiritus-sancti a.k.a. P. "Santa Leopoldina" #1. I have a plant that is
supposed to be this species - it does show most of the characteristics
described in the paper published on it, EXCEPT the petiole shape, which in
mine is markedly flattened on the upper surface, or hemispheric in
cross-section. The stem and petioles of this plant also flush scarlet at
times (in response to who knows what), and the leaves keep changing size,
although not shape. Although grown from a very small stem cutting, leaves
are now reaching over 20" in length - the distance between internodes is
extremely short (<1"), making the plant look almost like a self-header.
Oddly, for a Philodendron, it seems happiest at cooler temperatures.
What I am curious about is whether the plants illustrated in Exotica and
Tropica and labelled P. Santa Leopoldina are, in fact, P. spiritus-sancti.
My plant is almost a dead ringer for both of these two, so if it's in fact
something else that's for sale at the neighborhood Home Depot for 4.99 -
PLEASE BE GENTLE.