The giant salamanders of China—hulking amphibians that were once widespread across the country—are facing a dire conservation crisis. Prized for their meat and purported medicinal properties, the animals have been transported in droves to farms and virtually depleted in the wild. But conservationists may have to rethink their efforts to save China’s giant salamanders, which do not consist of a single species as experts have long believed. According to a new study published in Ecology and Evolution, there are in fact three species of Chinese giant salamanders, one of which may be the biggest amphibian in the world.
Researchers behind the new report conducted genetic analyses of 17 historical museum specimens, which were collected before the mass relocation of giant salamanders began, and tissue samples from critters that exist in the wild. The team was able to tease out three distinct lineages that diverged between 2.4 and 3.1 million years ago, a period when the Tibetan Plateau was rising rapidly and likely isolated the salamanders in unique landscapes, where they evolved into different species.
Once assumed to be the only Chinese giant salamander, Andrias davidianus arose in the Yangtze River. A newly identified species dubbed Andrias sligoi is unique to the Pearl River, and a third species is associated with Huangshan region. This last species remains undescribed because it is only known from tissue samples, according to CNN’s Ashley Strickland.
The researchers were able to get a better sense of the other new species, Andrias sligoi, because an exceptional salamander that lived at the London Zoo for 20 years has been preserved as a specimen at the city’s Natural History Museum. Measuring an impressive five feet and nine inches, this individual is the largest Chinese giant salamander ever recorded, reports Emily Chung of the CBC. As far back as the 1920s, experts suspected that it might belong to a unique species, and with their genetic study, the team behind the new research paper have confirmed the theory. What’s more, according to the researchers, Andrias sligoi is not only the largest of the Chinese giant salamanders, but also “the largest of the 8,000 or so amphibian species alive today,” according to the Zoological Society of London (ZSL).
“It’s amazing in this day and age that it took until now to work out what the world’s largest amphibian is,” Samuel Turvey, lead study author and ZSL conservation scientist, tells Douglas Main of National Geographic.
The researchers aren’t sure how to distinguish the three species anatomically because the museum specimens were preserved in different ways—some in liquid, some dried—which in turn makes it difficult to figure out what they looked like before the were moved around by humans. And it is difficult to find specimens in their native habitat. Original populations of Andrias davidianus “have been almost completely wiped out,” Turvey tells Chelsea Whyte of New Scientist. And the two new species, he notes, have similarly been “largely eliminated from the wild.”
The good news—sort of—is that all of the giant salamander species might very well exist on farms, “shortly about to be sent to restaurants,” Turvey tells Chung of the CBC. And knowing that Chinese giant salamanders are more diverse than previously assumed as important implications for their management. For instance, farmed giant salamanders are sometimes released back into the wild as part of conservation efforts, but the new study shows that care must be taken to restore unique species to their unique geographic environments.
“Each distinct species requires targeted and separate conservation management both to locate any surviving wild populations and hopefully to establish species-specific conservation breeding programs,” Turvey tells New Scientist.