Tree snails

Some snails enjoy the socialite life up in apartment buildings in the big cities; other prefer the simple life of living on tree trunks and leaves in the Amazon, as the one shown in the attached image. I have yet to figure out how this snail came to find a home on the leaf of a timbó plant, which is highly poisonous. Maybe it was just checking things out because when I returned to the scene today, it wasn't there.