Scientists Discover Nine New Species of Carnivorous Land Snails in the Remote Forests of Papua New Guinea

Nine recently discovered speciesA species is a group of living organisms that share a set of common characteristics and are able to breed and produce fertile offspring. The concept of a species is important in biology as it is used to classify and organize the diversity of life. There are different ways to define a species, but the most widely accepted one is the biological species concept, which defines a species as a group of organisms that can interbreed and produce viable offspring in nature. This definition is widely used in evolutionary biology and ecology to identify and classify living organisms.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>species of meat-eating land snails have been identified in the secluded forests of Papua New Guinea, known for its rich variety of species. A recent research paper details these tiny creatures, each so small that all nine could collectively rest on a U.S. nickel. These snails offer a unique chance to examine a rapidly vanishing group; globally, mollusks represent over half of the documented extinctions since 1500, with a significant number being land snails from the Pacific islands.

The island of New Guinea accounts for less than 1% of Earth’s land area, but it contains roughly 5% of the planet’s biodiversity and the largest intact rainforests in Australasia. Wildlife thrives within this large swath of undeveloped land, but Papua New Guinea’s old-growth forests are also highly desirable to loggers and are likely to become a conservation battleground in the future.

“These new species of snails were found in areas that still have native vegetation and still appear to be doing well, but they could easily become endangered if things change,” said John Slapcinsky, lead author of the paper and manager of the Florida Museum’s invertebrate zoology collection.

Challenging Exploration and Unique Snail Characteristics

To reach Papua New Guinea’s isolated forests, researchers had to travel on foot over steep mountains, sometimes using fallen trees to cross crevices that were more than 100 feet deep. There are few roads in the country, which historically posed a challenge to scientists interested in researching the region but has also shielded native plants and animals from human disturbance and habitat destruction.

Slapcinsky took nine trips to Papua New Guinea between 2002 and 2012, each time staying for at least a month to comb through the soil and fallen leaves. He ultimately collected more than 19,000 snails from over 200 sites.

Detailed photos of the snails, while beautiful, also serve a scientific purpose by providing documentation of the species. Credit: Florida Museum photo by Jeff Gage

Only 31% of the snail species he surveyed had been previously documented, a sign of Papua New Guinea’s high biodiversity and low levels of sampling. But the snails are also exceptionally hard to find because of their small size, pickiness about their habitats, and limited distribution. Nearly all of them are restricted to a single island or mountain.

The newly named snails have tightly coiled, Frisbee-shaped shells in various shades of brown and tan, some with attractive gold or brown flamelike bands. One of the new species, Torresiropa paterivolans, was named for its resemblance to flying saucers (in Latin, “patera” means “saucer,” and “volans” means “flying”).

Predatory Nature and Conservation Status

All nine species have dagger-shaped teeth on their radula, which is characteristic of predatory snails. Just what they’re eating, Slapcinsky said, is a mystery, since the snails did not eat anything under observation. Still, the shape of the teeth, combined with the fact that other species in the same family — Rhytididae — are predators, suggests that these newly discovered snails do eat meat.

There is not yet enough data to know the conservation status of the new species, but it is a promising sign that their habitat has not yet been dramatically altered by human activity.

The country of Papua New Guinea includes the eastern half of the island of New Guinea and several offshore islands. Credit: Florida Museum photo by John Slapcinsky

Slapcinsky contrasted this with the Hawaiian Islands, where native snails are at imminent risk of extinction. He works with a team at the Bishop Museum in Honolulu that collaborates with the state and federal government on captive breeding programs for native snail colonies, many of which harbor the last members of their species. They also provide native snails for fenced-in areas, known as exclosures, where predators have been removed and the native forest has been replanted. These are expensive programs that Papua New Guinea still has the chance to avoid, Slapcinsky said, by slowing deforestation and preventing the introduction of non-native predators before it becomes a more serious problem.

Snail Vulnerability and the Importance of Conservation

Snails are highly vulnerable to habitat disturbances because they cannot easily travel long distances and are usually adapted only to the environment in their immediate vicinity. “When these habitats are threatened, snails are often out of luck, since they can’t go anywhere,” Slapcinsky said.

Many past discoveries of new snail species, especially on Pacific islands, have come after it was too late to save them. Scientists did not know that many snails lived on Easter Island, which was completely deforested centuries ago, until examining fossil deposits. But species on the island of New Guinea can still be saved if the forest is saved. The newly named snails provide a rare glimpse at an ecosystem that remains largely intact, and there are surely many similar discoveries yet to be made.

“We don’t know everything that’s out there,” Slapcinsky said. “Most people may not realize how poorly known most of the invertebratesInvertebrates are animals that do not have a backbone. They make up the majority of the animal kingdom and include animals such as insects, worms, mollusks, and arachnids. Invertebrates are found in almost every habitat on Earth, from the depths of the oceans to the highest mountains. They play important roles in the ecosystem as decomposers, pollinators, and as a food source for other animals. Invertebrates have a wide range of body shapes, sizes, and behaviors, and they have evolved a variety of ways to survive and thrive in their environments.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>invertebrates are, even though 95 to 99% of all animals are invertebrates. You can go to a place, look around for a few months, and find all sorts of things that haven’t been described before.”

Reference: “Overlooked predatory snails from Papua New Guinea: nine new Torresiropa Solem, 1959 (Gastropoda: Stylommatophora: Rhytididae)” by John Slapcinsky and Ashley Elizabeth Murphy, 13 December 2023, Archiv für Molluskenkunde.
DOI: 10.1127/arch.moll/152/135-152

The study was funded by the National Science Foundation, the University of FloridaEstablished in 1853, the University of Florida (Florida or UF) is a public land-grant, sea-grant, and space-grant research university in Gainesville, Florida. It is home to 16 academic colleges and more than 150 research centers and institutes. University of Florida offers multiple graduate professional programs, including business administration, engineering, law, dentistry, medicine, pharmacy, and veterinary medicine, and administers 123 master's degree programs and 76 doctoral degree programs in eighty-seven schools and departments.” data-gt-translate-attributes=”[{“attribute”:”data-cmtooltip”, “format”:”html”}]” tabindex=”0″ role=”link”>University of Florida Foundation, and the University of Hawaiʻi at Mānoa.