When I found this plant – near the Pascoe River on Cape York Peninsula, northern Australia – I didn’t recognise it.
Eventually, I identified it as an unusual form of a species I have growing in my garden! The next image depicts the “normal” form (though with new growth as a bonus).
The “leaves” you see here aren’t leaves at all; they are flattened stems that serve as leaves by photosynthesizing. The true leaves are those little dark spots along the edge.
It is reasonably assumed that this growth form is an adaption to cope with harsh seasonal drought; the flattened stems are wilt-resistant.