A team of researchers from the United Kingdom, Canada and China has discovered there are not just one but three distinct species of Chinese giant salamanders. One of these species, Andrias sligoi, is possibly the world’s biggest amphibian.
The Chinese giant salamander (Andrias davidianus) is a species of salamander endemic to China, where it is a top predator in freshwater ecosystems.
These creatures were formerly distributed across a large area of central, eastern, and southern China and are recorded from 18 Chinese administrative regions.
They were historically eaten and used for traditional medicine in parts of southern China, and were sold for food from the historical trading center of Guangzhou to cities such as Shanghai, but were avoided and considered unlucky in other parts of their range.
Chinese giant salamanders have previously been considered a single species, Andrias davidianus.
However, a new analysis of museum and wild specimens reveals at least three distinct genetic lineages from different river systems and mountain ranges across China: Andrias davidianus, Andrias sligoi, and a third species which has yet to be named.
Andrias sligoi, which can reach 6.6 feet (2 m), is the largest of the three and is therefore the largest of the 8,000 or so amphibian species alive today.
Also called the South China giant salamander, this species was first proposed in the 1920s based on an unusual salamander from southern China that lived at the time at London Zoo.
Professor Samuel Turvey from the Institute of Zoology at the Zoological Society of London and colleagues used the same animal, now preserved as a specimen in the Natural History Museum after living for 20 years at the Zoo, to define the characteristics of the species.
The third, unnamed species, from Huangshan (the Yellow Mountains), is still only known from tissue samples and has yet to be formally described.
“Our analysis reveals that Chinese giant salamander species diverged between 3.1 and 2.4 million years ago,” Professor Turvey said.
“These dates correspond to a period of mountain formation in China as the Tibetan Plateau rose rapidly, which could have isolated giant salamander populations and led to the evolution of distinct species in different landscapes.”
“The decline in wild Chinese giant salamander numbers has been catastrophic, mainly due to recent overexploitation for food.”
“We hope that this new understanding of their species diversity has arrived in time to support their successful conservation, but urgent measures are required to protect any viable giant salamander populations that might remain.”
The team’s work was published in the journal Ecology and Evolution.
Samuel T. Turvey et al. Historical museum collections clarify the evolutionary history of cryptic species radiation in the world’s largest amphibians. Ecology and Evolution, published online September 16, 2019; doi: 10.1002/ece3.5257