Plant photographed in Southern Amazon.

Any ideas on this plant from the Southern Amazon?

 

That's a lemon tree or close hybrid, judging by the size of the leaves.

 

I don't think it can be a hybrid, as it was photographed in the middle of the Amazon jungle.

 

You'd be surprised how far plants travel. Lemons are native to China, so for that tree to have been in the middle of the Amazon, somebody would have had to bring it there. Hence it's just as likely that it's a hybrid lemon as it is that it's a species lemon - it would all depend on what was brought in and from where in Brazil. Both species and hybrid lemons are grown in South America.