In Michigan, specimens have mainly been collected from the southern half of the lower peninsula. (Burch and Jung, 1988)
In general, land snails are found in soil and leaf litter. Armed snaggletooth snails are commonly found living in rotten logs and leaf litter on calcium-rich soils, as well as beneath limestone outcroppings. In the Great Lakes region, this species was found to be a habitat generalist. More tolerant of dry conditions than other land snails, (Baker, 1939; Basch, et al., 1961; Burch and Pearce, 1990; Nekola, 2003; Riddle and Miller, 1988)may be found in prairie regions, although less commonly.
Armed snaggletooth snails tolerate relatively high temperatures, to about 44°C, particularly when previously acclimated to temperatures of 30°C. This species tolerates lower temperatures of -20°C. (Riddle and Miller, 1988; Riddle, 1990)
When fully extended, the soft body is almost as long as the shell, and is usually mottled. Armed snaggletooth snails have two pairs of tentacles, with eyes at the tips of the upper tentacles. Individuals of this species have a simple penis without an appendix and an unforked penial retractor muscle, and also possess female reproductive organs. Tricuspid teeth are located in the center of the radula, and are significantly narrower than the bicuspid lateral teeth. (Baker, 1939; Burch and Jung, 1988; Burch and Pearce, 1990; Pilsbry, 1948)
- Range length
- 3.0 to 5.0 mm
- 0.12 to 0.20 in
Land snails deposit their eggs in moist areas and secrete a substance to make the egg masses stick; eggs of this species are covered with a gelatinous, hydroscopic material. The time it takes for eggs to hatch depends on moisture and temperature; it may take longer for snails to reach maturity in drier areas. Eggs of this species are relatively large, averaging 1.0 to 1.2 mm in diameter. Maturity is usually reached when the lip of the shell is formed. (Burch and Pearce, 1990; Gugler, 1963; Tompa, 1984)
Land snails belonging to the clade Stylommatophora, such as armed snaggletooths, are hermaphroditic. Although they usually mate with other snails, they may also self-fertilize. Mating partners may be located by following mucus trails. After a courtship ritual, the snails will copulate, with each snail inserting spermatophores into the other. (Burch and Pearce, 1990; Gugler, 1963; Tompa, 1984)
- Mating System
- polygynandrous (promiscuous)
Generally, land snails breed in the warmer months of the year, and rain may bring on increased mating. Sexual maturity is likely reached when the lip at the aperture forms. In captivity, (Burch and Pearce, 1990; Gugler, 1963; Tompa, 1984)deposited loose clusters of 3 to 6 eggs on soil. In one study, armed snaggletooth snails were brought into a laboratory setting from solidly frozen soil; these individuals began to lay eggs within 8 to 15 days, indicating that this species likely lays eggs in the spring in the wild. Individuals in this study laid their eggs at night, retracting into their shells, depositing an egg into the body whorl, and pushing the egg through the aperture.
- Key Reproductive Features
- seasonal breeding
- simultaneous hermaphrodite
- Breeding interval
- Armed snaggletooth snails likely breed once a year.
- Breeding season
- Armed snaggletooth snails breed during the warmer months of the year.
- Range number of offspring
- 3 to 6
Land snails provide provisioning in their eggs and produce a gelatinous substance to cover them. They leave their eggs after they are deposited and there is no further parental care. (Burch and Jung, 1988)
- Parental Investment
Light intensity, relative humidity, and temperature influence much of a land snail's behavior, since these factors affect the snail's water retention. In general, land snails are nocturnal, and more active with increased relative humidity and decreased temperature. In temperate climates, snails may reduce their water content and form an epiphram over the shell aperture as they aestivate over the winter. During dry periods, this same membrane will form to prevent desiccation. Snails may also move in a "loping" fashion to avoid rough substrates or retain water. (Burch and Pearce, 1990; Pearce, 1989; Riddle and Miller, 1988; Riddle, 1990)
- Range territory size
- 10 (high) m^2
Communication and Perception
Land snails leave mucus trails, which are used as a form of communication. The mucus allows the snails to detect their own and other species. Some land snails may grow more slowly when exposed to mucus trails of the same species. The upper tentacles of stylommatophoran snails are sensitive to light and chemicals. Snails can find food in still air by following an olfactory gradient. Eyes at the top of the tentacles can detect light, and may also be used for sensing forms at night. Their anterior tentacles are chemosensory and their labia detect both touch and chemical signals. (Atkinson, 2013; Nordsieck, 2011; Pearce, 1997)
Pupillid snails (Family Pupillidae), such as armed snaggletooths, generally feed on fungi and decaying plant matter. The radula, a toothed feeding organ, is used to scrape or grind food. (Baker, 1939; Burch and Pearce, 1990)
- Other Foods
Specific predators are not known for this species, but in general, land snails are preyed on by lampyrid beetle larvae and other insects, birds, rodents, and small mammals, particularly voles and shrews. ("Illinois Snails and Slugs", 2009; Burch and Pearce, 1990)has denticles on its shells' apertures, which helps to protect its soft body.
Generally, land snails disperse fungal spores and plant seeds, and break down detritus in the forest. While many snails are vectors for nematodes, records for this particular species are not currently available in the literature. (Burch and Pearce, 1990)
- Ecosystem Impact
- disperses seeds
Economic Importance for Humans: Positive
There are no known positive effects ofon humans.
Economic Importance for Humans: Negative
There are no known adverse effects of armed snaggletooth snails on humans.
Armed snaggletooth snails do not have any special conservation status; however, NatureServe has listed this species as extirpated in Louisiana and vulnerable in North Carolina. More research and possible conservation efforts are necessary to combat this and ensure that other populations are stable. ("Gastrocopta armifera", 2013a; "Gastrocopta armifera", 2013b; IUCN, 2013)
Renee Mulcrone (author), Special Projects, Jeremy Wright (editor), University of Michigan-Ann Arbor.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
- bilateral symmetry
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
helps break down and decompose dead plants and/or animals
uses smells or other chemicals to communicate
an animal that mainly eats decomposed plants and/or animals
particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
- internal fertilization
fertilization takes place within the female's body
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
an animal that mainly eats fungus
- native range
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
- seasonal breeding
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
- tropical savanna and grassland
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
- temperate grassland
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
uses sight to communicate
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