On Exhibit posts
Among the roughly 1,400 species of land snails found in Cuba, those from the genus Polymita—that’s Latin for “many stripes”—are unique to the island nation. These tiny gastropods are quite aptly known as painted snails because of the variety of vibrant colors of their shells.
A dazzling array of painted snail specimens can be seen in the special exhibition ¡Cuba!, including Polymita picta, P. sulphurosa, P. versicolor, P. venusta, P. brochuri, and P. muscarum, all from the Museum’s collection.
It’s no surprise that land snails like Polymita would be so successful on an island. With the ability to secrete a mucus seal around their shell openings, these invertebrates can go dormant for long periods without drying out. This makes them good travelers, hardy enough to survive a trip at sea on vegetation that comes loose from the mainland during a storm or flood.
Painted snails are found in eastern Cuba, including throughout Alexander von Humboldt National Park, which stretches from the mountains to the sea on the northeastern coast of the island and is considered one of the most biologically diverse ecosystems in the world.
The beauty of these striped snails is a many-splendored thing, and differences in color occur not just between species, but also within individuals of a single species. Some scientists suggest that the variations might confuse predators, preventing them from homing in on these snails as a predictable meal, but the question is far from settled.
“Over a century ago, Charles Darwin and Alfred Russel Wallace argued about the purpose of zebras’ stripes,” says Mark Siddall, curator in the Division of Invertebrate Zoology. “We still don’t know the answer, save that it’s definitely not about camouflage—that was proven just this year. Obviously, we’re a lot further away from understanding the stripes on land snails.”
¡Cuba! is now on view and free for Members, and you can see more Polymita specimens among the mollusks in the Hall of Biodiversity.
A version of this story originally appeared in the winter 2017 issue of Rotunda, the Member magazine.
AMNH, American Museum of Natural History
February 10, 2017