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These are among the largest wild banana species (larger than any cultivated varieties), however they are more or less not in cultivation and are difficult to obtain.
Musa ingens is the largest published species at around ~15m.
Musa itinerans var. xishuangbannaensis, ~12m.
Musa jackeyi (could be a form of M. maclayi), ~12m.
Musa boman, ~10m.
Musa maclayi (multiple varieties), ~10m.
Musa peekelii (multiple varieties), ~10m.
There are reports of larger plants still, but they are unverified and may be new species or varieties. I hope this helps, if you are looking for specific info on any of them just ask if you can't find it.
This link has the descriptions of many published banana species. Not all of the names on the list are valid, but all of the names listed above are valid and some info can be found on each of them in this link
Musa home