The Spiny Slipper Snail, Bostrycapulus aculeatus (Gmelin, 1791), is the only local species of Slipper Snail (family Calyptraeidae) that displays distinctive sculptural features on its shell, in the form of scale-like spines, typically arranged along ribs that originate at the shell apex. The inch-long shell may be white, grayish, or brownish. As with other species of slipper snails, a shell septum separates the vital organs of the snail from its head and foot.
The Spiny Slipper Snail, Bostrycapulus aculeatus, from Sanibel Island. Photo by José H. Leal.