Flat-spired three-toothed snail facts for kids
Quick facts for kids Flat-spired three-toothed snail |
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| Conservation status | |
| Scientific classification | |
| Kingdom: | |
| Phylum: | |
| Class: | |
| (unranked): |
clade Heterobranchia
clade Euthyneura clade Panpulmonata clade Eupulmonata clade Stylommatophora informal group Sigmurethra |
| Superfamily: |
Helicoidea
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| Family: |
Polygyridae
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| Genus: |
Triodopsis
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| Species: |
T. platysayoides
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| Binomial name | |
| Triodopsis platysayoides (Brooks, 1933)
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| Synonyms | |
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Polygyra platysayoides Brooks, 1933 |
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The flat-spired three-toothed snail (Triodopsis platysayoides) is a special type of land snail. It's also called the Cheat three-toothed snail because it lives near the Cheat River in West Virginia. This snail breathes air and is a kind of mollusk found on land. It belongs to the Polygyridae family.
Contents
About the Flat-Spired Three-Toothed Snail
What Does It Look Like?
The snail's body is a light gray color. Adult snails have shells that are about 18–22 millimeters (about 0.7-0.9 inches) wide. They are about 8 millimeters (about 0.3 inches) tall.
The shell of Triodopsis platysayoides is thin and see-through. It coils to the right and has 5 whorls (turns). The shell is very flat. It has a wide, open hole in the center called an umbilicus.
The shell is light brown. The edge of the shell opening (called the peristome) is yellowish and has tiny dots. The opening itself is shaped like a long crescent moon. The lip around the opening is thick and white. There's also a thick, tongue-shaped "tooth" inside the opening.
How Scientists Classified This Snail
Triodopsis platysayoides is now officially recognized as its own unique species. It was first found by Graham Netting at Coopers Rock State Forest. Later, Stanley Brooks described it in 1933, calling it Polygyra platysayoides. The original snail specimen is kept at the Carnegie Museum of Natural History.
For a while, scientists weren't sure if it was a separate species. In 1940, Henry Augustus Pilsbry thought it was a distinct species. He also moved it to the genus Triodopsis. However, in 1968, another scientist thought it was just a subspecies of Triodopsis complanata. Most scientists didn't agree with this idea.
In 1974, evidence showed that it should be a full species. In 1988, studies confirmed that Triodopsis platysayoides is a valid species. It has unique body parts and genetic makeup. This was found by studying its foot tissue and comparing its family tree with other snails.
Where the Snail Lives
This snail species is endemic to the United States. This means it is found only in one specific area.
The flat-spired three-toothed snail lives only in West Virginia. It is found among sandstone rocks and boulders. These are located in a small area along the edge of the Cheat River gorge. The U.S. Fish and Wildlife Service has considered this snail threatened since 1978.
Snail Life and Environment
Daily Life and Activity
Not much is known about this snail's daily life. However, some information comes from a breeding program in West Virginia.
This snail is mostly active at night (nocturnal). It is most active in spring and early summer. This happens especially during cool, moist weather. The best conditions are when air temperatures are between 60 and 65 degrees Fahrenheit (15-18 degrees Celsius). The air also needs to be very humid (over 85 percent humidity).
During the day, these snails are usually found on the ceiling, walls, or floor of rock structures. At night, they are found equally on rocks and in the leaf litter nearby. They have been seen eating and resting under wet leaves next to rocks. They also move across the leaf litter to reach rocks. There are no known diseases that affect Triodopsis platysayoides.
Where the Snail Lives (Habitat)
The snail lives in cracks and small spaces in rocks. It also lives in the surrounding leaf litter.
During dry seasons, the snails hide deep inside large, broken boulders. These boulders are found just below the top of the gorge. Triodopsis platysayoides snails are usually seen within 1 meter (about 3 feet) of a rock. They can be found in cool, moist, deep cracks in shale, sandstone, and limestone rocks. They also live in talus (piles of broken rocks). The snail lives in different rock formations from the bottom of the gorge to the top.
Rock formations that are at least one meter (3 feet) tall can be good habitats. They need to have cracks and spaces that are at least one meter deep. The snail seems to prefer rock talus. However, it is also found in cliff areas with deep, dark cracks. When both habitats are present, the snail is more often found in the talus.
The types of plants and ages of trees around the snail's habitat can vary a lot. But some plants are often found there. These include sweet birch, rhododendron, and red maple. Some areas have very old trees, while others have young trees. The rock structure itself seems more important to the snail than the age of the trees or the plants growing on the rocks.
The direction of the slope also matters. North and northeast slopes in the Cheat gorge are naturally cooler and moister. South and southwest slopes need heavy canopy (tree cover) to provide shade and humidity.
What the Snail Eats
Triodopsis platysayoides eats many different things. Over 20 types of food have been recorded. These include old leaves and flower blossoms, fresh catkins, and fresh and old pack rat droppings. They also eat lichens, mushrooms, and even crickets.
Calcium might be hard for this snail to find. This is especially true for snails living among sandstone, which is often acidic. Triodopsis platysayoides has been seen eating old beech leaves and catkins. These are good sources of calcium. It also eats the shells of other snails like Triodopsis denotata and Mesomphix cupreus, and even its own kind.
Life Cycle and Reproduction
Adult snails are hermaphroditic. This means each snail has both male and female reproductive parts. When two snails mate, they both fertilize each other. Then, each snail can lay eggs. They bury their eggs in soil or leaf litter. In a group of captive Triodopsis platysayoides, small clusters of 3 to 5 eggs were laid in the soil under leaf litter during spring and summer.
Once the young snails hatch, they grow quickly. They can become adults within their first summer.
Triodopsis platysayoides is thought to be a relatively long-lived land snail. Based on the growth rings on their shells, these snails reach adulthood at 3 years old in the wild. In captivity, they can reach adulthood at 2 years old. About 33% to 67% of the snails found in the wild were adults.
Snail Population Numbers
Before 1981, only one small group of Triodopsis platysayoides was known. In 1972, about 50 snails were seen, and scientists estimated "several hundred" lived there. A later estimate in 1974 suggested 300 to 500 living snails. However, surveys at the same spot later found only 35 snails.
In 1984, 12 Triodopsis platysayoides were marked and released. But none of them were found again.
More snails were seen at Coopers Rock State Forest after a fence was put up. This fence helped control human access to the area. However, it's hard to know if the snail numbers are truly growing. Other snails with small populations can have big ups and downs in numbers (10 to 15 times).
Triodopsis platysayoides seems to be a common snail where it is found. Many other snail species live with Triodopsis platysayoides. But usually, Triodopsis platysayoides is the most common snail. Sometimes, there are more Triodopsis platysayoides than all other snail species combined.
Scientists have taken genetic samples from snails on both sides of the gorge. This helps them see if the snail groups are separate or connected. In 2007, this study was still ongoing.
Why the Snail is at Risk
Because this snail lives in such a small area, it is very vulnerable. Natural events or human actions could destroy most, or even all, of its populations.
Hikers can accidentally disturb the leaf litter. This can crush snails. Rock climbers can also harm snails and destroy their homes without knowing it.
Human activities like logging, building houses, and forest fires can all change the environment. These changes can make it hard for the flat-spired three-toothed snail to survive.
Protecting the Snail
Efforts to help this animal include fencing off its habitat. About 1,100 acres (4.45 square kilometers) of snail habitat have also been bought. The fence is not to keep snails in, but to keep people out of their living areas.
The West Virginia Division of Natural Resources is working with the U.S. Fish and Wildlife Service. They are creating a "Safe Harbor Agreement" for the snail on their lands. They are also working with private landowners. They encourage them to protect the snail by using special rules for managing timber.
The state of West Virginia, the Nature Conservancy, private landowners, and the U.S. Fish and Wildlife Service are all working together. Their goal is to prevent the flat-spired three-toothed snail from becoming extinct.
This article incorporates public domain text (a public domain work of the United States Government) from references.
See also
In Spanish: Triodopsis platysayoides para niños
