As nearly everyone knows, I get longwinded esp. regarding Utricularia. So
I'll keep this very short. Aside from a variety of other differences between
the two species (steady boy, no reason to enumerate them!) U. reniformis has
much larger leaves than nephrophylla, as least if grown well. While U.
nephrophylla's leaves rarely get much bigger than 3 cm across (the big
leaves you're getting are quite admirable), the leaves of reniformis
can get large enough to cover a good fraction of your computer screen!
(Unless you're using a sun, then maybe a typical window). I'd like to
say more, but I better not. My clone of U. reniformis is recently acquired,
and is pondering if life is worth living. The stolons are thick and crisp,
like fresh mung bean sprouts.
BAMR
Wow! That was short!