Genetic work published from 2018 onwards found that populations of Andrias davidianus across Chinese river basins are deeply divergent, corresponding to separate evolutionary lineages rather than one connected species. Several have since been formally described, including Andrias sligoi, the South China giant salamander, and additional lineages remain under study.
The finding complicated conservation immediately. Chinese farms hold millions of animals bred from mixed stock, and releases intended as restoration have moved farmed animals into basins where the local lineage was different. Genetic surveys of released and wild-caught animals have found lineage mixing widespread, so a released animal cannot be assumed to belong where it is placed.
A common shorthand calls this species the world's largest amphibian at up to 1.8 metres. The maximum is real but exceptional; most measured wild animals are far smaller, and the very large historical specimens come from a period before the population collapse.