Along with many land snails, Mesodon zaletus are hermaphroditic, otherwise called monoecious (Foster, 1996; Stiven, 1996) meaning they possess both male and female sexual organs within the individual (Dourson, 2006). This could be beneficial so they do not need to search for another snail to mate with and 100 percent of its genes would be passed to its offspring.
Spring to early summer are their optimal mating periods (Foster, 1996; Stiven, 1996) where they typically lay 15 to 100 eggs within collections of dead leaf material (Foster, 1996; Stiven, 1996). This may be necessary because it provides the right conditions for their offspring to grow. According to Bradley Foster and Alan Stiven, two Biological Scientists who put together research on different organisms including snails, it can take up to two years to reach adult size (Foster, 1996; Stiven, 1996). They also found no relationship between body size or age on the number of eggs produced (Foster, 1996; Stiven, 1996).
A trait that is shared between land snails, including Mesodon zaletus, is that the juvenile snails undergo direct development, which means they produce miniature snails that lack a larval phase (Wilbur, 1984). The juvenile typically hatch throughout the summer (Foster, 1996; Stiven, 1996). Summertime would probably seize weather conditions that provide high moisture, which is where they prefer to lay their eggs and live.
As mentioned before, Mesodon zaletus has both the male and female reproductive organs. The penile structure is long with round ends containing many cells with vacuoles, including two rectangular structures known as pilaster and multiple diverticulae or pouches (Cookson, 1982). According to Henry A. Pilsbry, a Biologist and Malacologist, or one who specializes in mollusks, found that one pilaster tends to be shorter than the other (Pilsbry, 1940). It also has a large retractor muscle that connects to the penis above the junction possessing the vas deferens and is surrounded by adventitious connective tissue (Cookson, 1982). Adventitious connective tissue is a tissue that mainly functions to provide support for structures and organs.
The female reproductive structure, or the vagina is elongated and slender with simple columnar and simple cuboidal epithelium (Cookson, 1982). There has not been much research on the vagina, but one specimen that was studied by Pilsbry found that the vagina of that Mesodon zaletus was 5.5 mm in length (Pilsbry, 1940).
The genital atria in both the penis and the vagina is made up of longitudinal muscle filaments and is surrounded by simple cuboidal and columnar epithelial tissues (Cookson, 1982). Both these types of tissues line many organs in the human body as well like the intestine.
