A new genus and species of mid-Oligocene nimravids have been identified from fossilized remains found in northern China. This discovery fills a gap in knowledge about the family Nimravidae in eastern Eurasia.
Life reconstruction Taotienimravus songs in the style of Chinese painting. Image credit: Yuefeng Song.
Taotienimravus songs lived in what is now China during the Middle Oligocene, approximately 28 million years ago.
The ancient species belongs to Nimravidsan extinct family of saber-toothed hypercarnivores, sometimes called false saber-toothed cats.
“The order Carnivora exhibits one of the widest ranges of body size diversity among mammals, starting at around 50 g for the smallest weasel. Mustela nivalis on average more than three tons in pinnipeds Mirunga” said Dr. Qigao Jiangzuo from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences and colleagues.
“With a few exceptions, such as the Ursidae, large-bodied terrestrial carnivores, especially those weighing more than 20 kg, typically have a macrocarnivorous diet, preying on large animals of comparable or larger size.”
“The family Nimravidae, commonly referred to as false sabertooths, represents one of the earliest divergent lineages of carnivores, characterized by large body size, hypercarnivorous craniodental morphology, and a presumably macrocarnivorous diet,” they added.
“The earliest confirmed fossils of this family in the Middle Eocene belong to already highly specialized species with feline craniodental morphology.”
“Nimravids underwent radiation during the Eocene-Oligocene, with the best-preserved records found in North America, where numerous skulls and complete skeletons have been discovered.”
“Fossils are also widespread in Eurasia, but they are less well preserved.”
“As the first lineage of Carnivora to evolve a large body size, Nimravidae are an ideal group to study the acquisition of the early macrocarnivorous niche of Carnivora in an ecological context significantly different from that of the modern world.”
Skeletal remains Taotienimravus songs were discovered in the Qingshuying Formation in northern China.
Analysis of the specimens revealed that the new species is a non-saber-toothed ecomorph with an initial adaptation for bone splitting—a unique form among the family Nimravidae.
The animal likely had a killing behavior that differed from that of other feline predators, but probably used a tearing bite, as seen in hyenas.
“The most distinctive features of the new nimravidae are the very short and strong upper canines and the generally wide palatal region,” the paleontologists said.
“The rostrum is very wide, probably one of the widest among known nimravids.”
“Unlike many other feline carnivores, the premolars do not decrease in size but instead enlarge, leaving no diastema between the canines and cheek teeth.”
“This contrasts with the condition of most feline carnivores, which almost always have a diastema.”
“We interpret this gap as correlating with the dog's strong bite and the use of the fangs to penetrate deeply into prey.”
The team's phylogenetic analysis revealed Taotienimravus songs within Nimravinae, where it forms the sister lineage of European and North American Nimravus And Dinelurus.
This clade is sister to the European lineage. Eofelis + Dinalurictes + Quercilurus.
“The increase in body size among Nimravidae appears to have coincided with the extinction of Oxyaenidae, another Paleogene predatory clade,” the researchers said.
“The initial emergence of a macrocarnivorous adaptation in Carnivora via a feline ecomorph likely reflects competitive dynamics.”
“Nimravids successfully occupied several ecological niches that were not exploited by felids, likely due to the lack of competition within carnivores for most of their evolutionary history.”
“Our study highlights the role of both abiotic and biotic factors in shaping niche availability for these animals, highlighting the need to discuss niche change and evolution based on these considerations.”
A paper a description of this discovery was published on November 26, 2025 in the journal Proceedings of the Royal Society B.
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Qigao Jiangzuo etc.. 2025. A new ecomorph of Nimravidae and early acquisition of a macrocarnivorous niche in Carnivora. Biological Sciences Educational Process 292 (2059): 20251686; doi: 10.1098/rspb.2025.1686
