Somewhere in the lowland Atlantic Forest of Espírito Santo state, on a slope that has probably been logged twice since anyone bothered to count, a philodendron is growing that most collectors would trade significant money — and a little dignity — to own. Its leaves run to sixty centimeters or more, a matte, heavily bullate surface the color of a storm cloud, the lateral veins sunk so deep they look like they were pressed in with a thumb. The petiole is round, pale, faintly glaucous. There is nothing else in the genus that looks quite like it in person. Photographs, and there are very few good ones, do not adequately explain why people lose their minds over it.
The plant is Philodendron spiritus-sancti, named for the state where it was first collected. The botanical record shows it described from a small population; current field estimates, depending on who is counting and how optimistically, place the number of mature wild individuals somewhere between six and a few dozen. The IUCN lists it as Critically Endangered. In the hobby, it sells — when it sells — for prices that would buy you a used car. Both of those facts are true simultaneously, and sitting with both of them is the only honest way to talk about this plant.