Both of these look like Musa yunannensis, one has not yet developed the darker color on the petioles and pseudostem yet. The strong waxyness on the dark green pseudostem and petioles is indicative of yunannensis. The waxyness will rub off white on the contacting surface. Musa itinerans itinerans does not have the waxyness that rubs off, and has a Bronze rather than a dark coloration on the pseudostem.
I do not yet know how to determine the differences between the four subspecies of yunannesis, though I think it may be hand and bunch sizes.
I have limited experience with this species. I hope this helps.
Musa yunannensis
Musa itinerans itinerans
I have other pictures of these at various growth stages in my photo gallery. Neither species likes temperatures above 90F, both stop growing at those temperatures.
