Melongena patula has a shell that reaches a length of 75 – 250 mm. The surface of this shell shows a deep chestnut brown color lined with a few white or yellow spiral bands. The interior is white. The shell is quite slender, sometimes spiny on the shoulders, with a wide aperture. This species can be found from the Gulf of California (Mexico) to Peru. These sea snails live in shallow water, usually in sandy or muddy areas, especially under mangrove trees.