Vertigo modesta (Cross Vertigo)




Terrestrial gastropods do not move much, usually only to find food or reproduce (NatureServe, 2010).  Because of this I will focus on those two aspects of this animal’s life.


Although specific nutritional information regarding Vertigo modesta is lacking, most land snails are generalist herbivores (Lee, 2007). Land snails can also function, however, as mycophagists (fungi eaters), detritivores, and some snails even as carnivores, consuming insects, nematodes, earthworms, or other gastropods (Martin, 2000). Olfaction is the primary sensory behavior utilized to find and move toward a food item (keeping in mind that this movement is small, on the scale of centimeters to meters) (NatureServe, 2010).


There is also a deficit of information regarding the reproductive behaviors of Vertigo modesta specifically.  In general, land snails exhibit a diverse array of sexual systems and reproductive strategies, behaviors, and even anatomical differences (Martin, 2000).  Many of these land snails, including Vertigo modesta, are hermaphroditic exhibiting both male and female sex organs.  Although self-fertilization could occur, it is most common that these individuals take part in reciprocal mating (out crossing) in which both individuals act as the male and female during copulation (Lee, 2007).  During this process sperm are transferred from one individual to the other and then store either in a viscous mass or in a discrete packet called a spermatophore, where the sperm can remain viable for quite some time (Martin, 2000).  Land snails can be oviparous (i.e., lay eggs), or ovoviviparous (i.e., eggs develop inside the mother and the young are “born live”) (Lee, 2007).  Most of Maine’s terrestrial gastropods, which includes Vertigo modesta, are oviparous and are likely to lay their eggs in pockets of moist soil or under stones, logs, wood, or leaf litter (Martin, 2000).