Thanks @SenexRugosus . I agree with Matt that is likely a yellow form of D. sulphurea. D sulphurea can reproduce vegetatively so the resulting daughter tubers/plants would also exhibit the same colouration as the parent plant. A characteristic of D sulphurea is that the callus on the midlobe has a single ridge, I think that is what I am seeing in most of your photos.
I’ll try to separate them and would need to create anew record for one I think. I can no longer see the duplicate option available. If I can the new record may end up on your list again, thanks
Yes, they are all pure yellow. There is a a colony of sulphurea about 10 metres away, all with typical sulphurea coloration. I can take more photos of particular features if that would help the ID.