The snail of interest, Neohelix major, is a hermaphroditic species, meaning that it possesses both male and female reproductive anatomy (Cuezzo, 1990). As far as anatomical points of interest, Neohelix major possesses male organs which include the penis, and vas deferens, while the female organs consist of a vagina and a free ovary (Cuezzo, 1990). The reproductive system of Neohelix major also contains the ovotestes and the hermaphroditic duct (Cuezzo, 1990). Because these organisms possess both male and female anatomy, they are capable of performing cross fertilization which is the fertilization of an organism by male and female gametes of the same species (Hickman, 2012).Like other members of the Stylommatophora clade, Neohelix major is able to self fertilize in the case of severe isolation and still produce fertile offspring (Wilbur, 1984).

            Reproductive system of a gastropod. From wikipedia commons


MG - mucus glands

P - penis

AG - albumen gland

HD - hermaphroditic duct

OT - ovotestis

SO - spermoviduct

VD - vas deferens


The reproductive journey begins at the ovotestes, which is a hermaphroditic reproductive organ containing tubes that house both male and female gametes (Cuezzo, 1990). At around 13 weeks of life, when the individual is mature sexually, the sperm moves from the tubules into the hermaphroditic duct (Cuezzo, 1990). Eggs from the albumen gland travel through the free ovary while sperm travels out of the hermaphroditic duct and into the vas deferens, where they run parallel to the eggs in the partially segregated spermoviduct (Cuezzo, 1990).

Just as in the other members of the Polygyridae family, when the fertilization occurs, it can be either internal or external (Emberton, 1993). Sperm can be deposited without the penis being inserted which results in either internal or external sperm exchange.

   Fertilization occurs in snails of the Stylommatophora clade after a bout of courtship that then results in a fast transfer of sperm (Wilbur, 1984).  When fertilization occurs in members of the Stylommatophora clade such as Neohelix major, the individual deposits eggs (Wilbur, 1984). To ensure that they have the highest survival rate possible, the eggs will most likely be laid in a damp place such as under a log or a moist area of brush and leaves (Wilbur, 1984). The most common reason eggs do not survive is due to drying out (Wilbur, 1984).

Terrestrial gastropods have a direct life cycle, meaning that the eggs that hatch do not have a larval stage, and emerge as juveniles that are very similar to their adult counterparts (Hickman, 2012).

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