Sinningia cardinalis

A seedling sinningia forms a tuber very early in its development.  This is a young plant of Sinningia cardinalis, with the tuber already visible as the brown swelling at the base of the stem.  When the tuber first forms, it is green, and only turns brown as it develops.

A picture of an even younger seedling (of S. aghensis) can be seen here.

Cardinalis: seedling with tuber

Cardinalis: tuber

The Dancing Tuber

Is this a horse?  A camel?  A sheep?  Whatever, it's doing a spiffy samba.

It may look odd, but it has all the tuber elements: roots at the bottom, shoots at the top, in the "axils" of last year's stem stubs.

Because of its elongated shape, it looks more potato-like than most sinningia tubers, but to be a real potato, it would have to have buds ("eyes") scattered along its length, instead of being clustered at the top.