Patera pennsylvanica

Reproduction

 

There is very little reproductive information pertaining to this species of snail. Henry Pilsbry discussed the genital anatomy of Mesodon pennsylvanicus (a synonym for Patera pennsylvanica) but the exact way in which this species reproduces has either not been researched or has yet to be reported (Pilsbry 1940). Because this information has not come to the forefront, I will discuss the general reproduction of the Stylommatophora, or terrestrial, snails. 

Most land snails are simultaneous hermaphrodites. This means that each individual snail contains the sexual organs of a male and a female, simultaneously (hence, “simultaneous hermaphrodites”) (Wikipedia contributors 2012), and both male and female sex organs within the species are fully functional (Chase 2007). While some terrestrial snails are capable of self-fertilization, it should never be an assumption that this is the case with every species. Some hermaphroditic snail species lack the ability to self-fertilize because the sperm and egg cells mature at different times (Robert Nordsieck 2011). Self-fertilization is an advantage for species with small populations (Hotopp and Pearce 2006).

Some land snails engage in courting rituals that can last up to half of a day (Information and Facts about Snails 2012). One way of courting is the practice of coating each other in slime which may make the process of mating easier (Information and Facts about Snails 2012).
Hermaphroditic snails store sperm within a structure called a spermatophore. The sperm is transferred via one snail’s penis into its mate’s vagina through an opening behind the right tentacle, called the “genital pore” (Hotopp and Pearce 2006). After depositing the spermatophore the sperm is released and the male and female gametes come together in the fertilization chamber (Hotopp and Pearce 2006). Once the egg is fertilized it is passed into the spermoviduct and coated with a substance called albumen which aids in feeding the snail through this development process as well as giving the egg a protective coating (Hotopp and Pearce 2006). Afterwards the egg or eggs are deposited in a moist area or the parent digs a hole in which to deposit its offspring (Hotopp and Pearce 2006). 

In some climates reproduction is linked to the seasons or favorable weather (Hotopp and Pearce 2006). In weather that is incompatible with some snail species they may become inactive and seal themselves into their shells with a thick layer of dried mucus called a epiphragm (Hotopp and Pearce 2006). 
Most terrestrial snails go through direct development, meaning that when the young are hatched they resemble the adult specimen. 

Interesting tidbit of information learned: Some snails are capable of changing their sex in later life. For example, some species can be male with the capacity to move about in its early life and then later in its life it changes into a sessile female. In other species the same transition may occur except the female stage remains mobile (Robert Nordsieck 2011). 

See how the species Patera pennsylvanica interacts with other species. Or return to the home page.