Wildlife Spotting

Treehopper

It's some kind of leafhopper nymph. You can see its wingpads, they look pretty developed, so it's probably a later instar. I wish I had some keys or resources about Brazilian insects, but sadly, I do not. Try searching around on google images and other places. It might be tough, the leafhoppers aren't as popular as butterflies or grasshoppers, so they're tougher to identify. But not impossible!

then it should be a specific sort of a flea - i bet on that. (no idea which one specifically, though...sry)

Its like small Grasshopper. I find similar insects sit on my shirt while boating at seashore. They are harmless.