Cuvieronius hyodon. Illustration and photo-reconstruction of the ancient proboscis Cuvieronius hyodon walking along a track in the American jungle. Cuvieronius is an extinct New World genus of gomphothere. It stood 2.7 metres tall and looked like a modern elephant, except for its spiral-shaped tusks. This animal initially evolved in North America about 10.3-10.2 Mya. During the Great American interchange of around 3 million years ago, Cuvieronius and two species of its sister genus Stegomastodon moved south into South America. They were the only proboscid mammals to colonize South America.