The Catesby Risso
The Catesby Risso, Schwartziella catesbyana (d’Orbigny, 1842), is one of the relatively common micromollusks found in Southwest Florida and other areas of the Western Atlantic. The elegant little shell measures about 4 mm (0.16 inch); the shell of a living snail is transparent , but becomes opaque after the animal dies. Fresh dead shells are often translucent. Micromollusk shells may be collected using a method that involves collection of shell-rich sand, which, after drying and sorting using a hand-lens or small microscope, may yield a number of different species . Try it yourself!
Catesby Risso, Schwartziella catesbyana. Photos by José H. Leal.