Chris Simms.
The smallest land snail is called Angustopila psammion.
Contributions to zoology
The smallest snail found on land is a new species. The shell volume of the psammion is only 0.036 millimetres and it has a shell just 0.48 millimetres high. The species is so small that you could fit about five individuals inside the average grain of sand.
These snails are hard to see. To find them, Barna Pll-Gergely and his colleagues gathered soil samples from caves and placed them in a bucket of water. They sieved the debris, dried it, and examined it under a microscope. Pll-Gergely cleaned the shells under the microscope with brushes used by nail artists.
Pll-Gergely says the snails probably didn't live in the caves. The shells of surface-dwelling shrews are what we assume the sediment came from through the crevices. The living snails live in limestone crevices.
The Ancient Greek word for "dung gatherer" is what the researchers named the snail after. It seems that it has a pattern of radial lines on the surface of its shell, which may be its own faeces.
The coprologos seems to decorate its shell with its own feces.
Contributions to zoology
It's not known why it does this. Pll-Gergely says what would prey on the tiny snails if it was camouflage. If not camouflage, what? It was surprising to see that the tiny snails have complex behavioural mechanisms that evolved as a response to certain environmental factors that we don't know about.
The small snails give them advantages. Pll-Gergely believes that the small snails can reach food particles and enter narrow rock crevices. He says that they could avoid being eaten by their predator by being smaller.
The world's loneliest snail can't get a date.
Is the smallest land snail possible? Pll-Gergely says it will be difficult to find anything smaller.
There is a record holder for the smallest known snail in the sea, with a diameter of between 0.24 and 0.46mm. That is close to the lower limit, which is determined by the number of neurons a newborn snail must have to be functional, and the shell of the adult snail being large enough to accommodate at least one egg.
The journal has a reference to Contributions to Zoology.
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