Looks like 'Immense'. Can get quite large.

Now that asking won't unnecessarily bump this discussion (except in the right direction,) I'm curious as heck if those red petiole stripes/spots are common on rhiz. Begonias? I would want to put this plant above my head! It looks hand-painted.

BTW, your Sans looks quite healthy and vigorous, nice!

Not all rhizos have red hair/bumps. Immense is a hybrid of Ricinifolia which is a hybrid of heracleifolia and barkeri. The red hairs probably come from heracleifolia.

U043 has some very pronounced "bumps" on its petioles which is its sole redeeming quality (IYAM).

I like it, none of the rhizomatous ones I've seen or had were so prettily decorated!

Here is my old Cachuma. Wished I could find another one.

View of the whole plant.