Philodendron sp. "Chumley Curly"
This plant is sometimes called "miniature selloum" although it is not really a miniature at all. I call it the Chumley Curly because Robert Chumley discovered it and because the leaf divisions curl under the leaf. In size it is smaller and more compact in habit than typical P. bipinnatidifum (aka selloum) plants, but doesn't approach what I would call a "miniature".
The picture above shows Robert Chumley holding a leaf of the Chumley Curly while at one of the International Aroid Society annual shows. This gives one a good idea of the size of the leaves on this plant.
Although I have never had a Chumley Curly in my breeding collection, I have been able to work with progeny from crosses done by Robert Chumley. He used a cross of P. bipinnatifidum and P. speciosum as one parent and the Chumley Curly as the other parent. Robert gifted me with two plants from two different crossings so I call one the "curly-evansii F1 G1"; with the G1 denoting that is was from the first of the crosses, and the second is "curly-evansii F1 G2" for the one from the second of the crosses.
I've since done F2 and F3 generations using the G1 in an effort to get the Chumley Curly to show up in the progeny. So far I have very interesting and attractive plants from these attempts, but no clear throwback to Chumley Curly has yet shown up.