Triodopsis tridentata is a hermaphroditic snail, meaning it has both male and female reproductive organs (Speiser, 2001).  The Northern Threetooth snail is monoecious, which means it possesses both male and female sex cells (Hickman, 2009). Although this snail has both sex cells, it does not self-fertilize (Martin, 2000). When two snails mate, they play both the roles of a female and a male in the relationship, exchanging sperm into each other (Martin, 2000). To prevent self fertilization, the sperm packets are exchanged in bundled  spermatophores (Martin, 2000). Spermatophores are capsules or packets enclosing sperm that are produced by males (Hickman, 2009).

After the exchange of sperm has occurred,  the sperm is stored inside the snail to fertilize the eggs right before they are laid (Martin, 2000). Triodopsis tridentata prefers to lay their eggs under wood and loose debris on the forest floor (Barker, 2001)