Slightly off subject...but...while on subject of the jungle rivers....there was an American couple who ventured through the Amazon River on a boat. They had already been there a few days.
While on the boat, the top of his head was itching. It began to itch so bad no scratch or anything he did could cure it. His wife finally looked at it (he was balding) and there was a lump in his scalp moving. It finally burst open and a creature squirmed out, which then flew away.
Its known as the Botany Fly.
Yuck!!