Sphaerospira informis Mousson is one of Australia's largest land snails. It's outdone by a handful of species—Hadra bipartita of Far North Queensland and Hedleyella in southern Queensland and northern New South Wales. Few others get close.
It lives in rainforests in mid-east Queensland from about Mount Dryander (near Prosperine) to Sarina. Broken shells are common. It seems that everything likes to feed on them. Not surprising, really. Any predator that landed one of these snails would dine like a king.
Something else that's not surprising is that they're good at hiding. They lurk under logs and leaves, emerging only at night or during heavy rain. I picked up this shell (sans inhabitant) near Teemburra in the Eungella region. I'm not sure what killed the snail. No doubt, some animal version of Mr Creosote was slumped against a nearby stone calling desperately for a bucket.