Physical Appearance

Zonitoides species have a flattened shell in a heliciform (spiral) shape (White-McLean, 2011).  Shells of these invertebrates are commonly described as “umbilicate,” meaning that it they have a central indent resembling a navel.  Adult snails of the genus Zonitoides have shells that are less than one centimeter in diameter and about two to four millimeters in height (Pilsbry, 1946).

         Photo courtesy of Jeffrey Nekola and Matt Kuchta.       Photo courtesy of Jeffrey Nekola and Matt Kuchta.

Z. limatulus can be distinguished from similar species by its shell.  This species has a shell that is round and widely umbilicate, meaning that it has a deep indent in the center of its 4 ½ whorls (Dourson, 2010).  It is white to corneous in color and has a dull appearance, which are two characteristics that easily set it apart from close relatives such as Z. nitidus, the black gloss snail (Burch, 1962).  This snail’s shell also has distinct growth lines near the top, which fade near the shell’s base (Burch, 1962). The shell of a mature dull gloss snail is 2 to 3 millimeters in height, and 4.3 to 5 millimeters in diameter (Pilsbry, 1946 and Wisconsin DNR, 2011). Overall, it is distinguished from other species of Zonitoides by the more lusterless surface of its shell, hence the common name, "Dull Gloss" (Pilsbry, 1946).

What is the habitat of Zonitoides limatulus?