This third type was called "square" bananas by our Costa Rican guide. We saw them on the Osa Peninsula in very remote Corcovado National Parque. They were located only along the coastal trail inland about 100 meters and for at least 10 miles. I suspect they were planted as a settlers' food source when they were making the long journey up the coast.
Most fruits were not consumed by humans anymore. Our guide said he often saw Peccaries, Tapirs, Monkeys, coati Mundis, and other animals enjoying the ripe fallen bananas.
They look like our old friend Orinicos. Any other opinions?
one more pic...
