page_title: Land snail
section_title: Reproduction
hierarchical_section_title: Land snail / Biology / Reproduction
caption_attribution_description: English: Two snails inspect each other prior to mating. Photograph taken with Yashica D-series Twin-lens reflex camera. Helix aspersa, determined 04 June 2011 by Francisco Welter-Schultes.
context_page_description: A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. Land snail is the common name for terrestrial gastropod mollusks that have shells. However, it is not always easy to say which species are terrestrial, because some are more or less amphibious between land and fresh water, and others are relatively amphibious between land and salt water.
  Land snails are a polyphyletic group comprising at least ten independent evolutionary transitions to terrestrial life. The majority of land snails are pulmonates that have a lung and breathe air. Most of the non-pulmonate land snails belong to lineages in the Caenogastropoda, and tend to have a gill and an operculum. The largest clade of land snails is the Cyclophoroidea, with more than 7,000 species. Many of these operculate land snails live in habitats or microhabitats that are sometimes damp or wet, such as in moss.
  Land snails have a strong muscular foot; they use mucus to enable them to crawl over rough surfaces and to keep their soft bodies from drying out. Like other mollusks, land snails have a mantle, and they have one or two pairs of tentacles on their head.
context_section_description: The great majority of land snails are hermaphrodites with a full set of reproductive organs of both sexes, able to produce both spermatozoa and ova. A few groups of land snails such as the Pomatiidae, which are distantly related to periwinkles, have separate sexes: male and female. The age of sexual maturity varies depending on species of snail, ranging from as little as 6 weeks to 5 years.  Adverse environmental conditions may delay sexual maturity in some snail species.
  Most pulmonate air-breathing land snails perform courtship behaviors before mating. The courtship may last anywhere between two and twelve hours. In a number of different families of land snails and slugs, prior to mating one or more love darts are fired into the body of the partner.
  Pulmonate land snails are prolific breeders and inseminate each other in pairs to internally fertilize their ova via a reproductive opening on one side of the body, near the front, through which the outer reproductive organs are extruded so that sperm can be exchanged. Fertilization then occurs and the eggs develop. Each brood may consist of up to 100 eggs.
  Garden snails bury their eggs in shallow topsoil primarily while the weather is warm and damp, usually 5 to 10 cm down, digging with their foot. Egg sizes differ between species, from a 3 mm diameter in the grove snail to a 6 mm diameter in the Giant African Land Snail. After 2 to 4 weeks of favorable weather, these eggs hatch and the young emerge. Snails may lay eggs as often as once a month.
  There have been hybridizations of snail species; although these do not occur commonly in the wild, in captivity they can be coaxed into doing so.
  Parthenogenesis has been reported only in one species of slug, but many species can self-fertilise.
caption: Two Helicid snails make contact prior to mating.
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