An artist's illustration of what a newly discovered extinct species of giant otters looked like. Remarkably preserved fossil remains, dating back about 6.24 million years, were found in the Yunnan Province of China. Cleveland Museum of Natural History

An extinct species of otters that weighed over 100 pounds and was as large as modern-day wolves was discovered in China recently, researchers announced Monday. Named Siamogale melilutra, the giant otters lived in the Yunnan Province about 6.24 million years ago.

Unusually for findings that date back so long ago, researchers found a complete cranium, mandible, dentition and other parts of the skeleton, making their job of identifying the species as new to science easier. The rich haul also allows them to study the species in detail and determine its taxonomic classification, history of its evolution and functional morphology.

Denise Su, curator and head of paleobotany and paleoecology at the Cleveland Museum of Natural History, who co-authored a paper on the finding, said in a statement: “While the cranium is incredibly complete, it was flattened during the fossilization process. The bones were so delicate that we could not physically restore the cranium. Instead, we CT-scanned the specimen and virtually reconstructed it in a computer.”

She and Xiamong Wang, curator and head of vertebrate paleontology at the Natural History Museum of Los Angeles County, and co-author of the paper, found the species had features now found in both otters and badgers, which gave it its name. Melilutra is a combination of the Latin names for badger (meles) and otter (lutra).

By studying S. melilutra, the researchers think that otter teeth, suited to eat hard-shelled animals like crabs, clams, mussels and so on, evolved similarly among different species not because they share a common ancestor but because they lived in similar environments — a phenomenon called “convergent evolution.”

The fossils were recovered from a lignite mine in the Shuitangba region of Yunnan Province in south China.

The study, titled “A new otter of giant size, Siamogale melilutra sp. nov. (Lutrinae: Mustelidae: Carnivora), from the latest Miocene Shuitangba site in north-eastern Yunnan, south-western China, and a total-evidence phylogeny of lutrines,” was published Sunday in the Journal of Systematic Palaeontology.