[PaleoMammalogy • 2025] Taotienimravus songi • A New ecomorph of Nimravidae, and the early Macrocarnivorous Niche Exploration in Carnivora

 

 Taotienimravus songi

 Jiangzuo, Lyras, Grohe, Werdelin, Niu, Huang, Li, Jiang, Fu, Wan, Liu, Wang & Deng, 2025

DOI: doi.org/10.1098/rspb.2025.1686 

 Artwork by Yuefeng Song.

 

Abstract

Here, we describe a new ecomorph of Nimravidae, Taotienimravus songi gen. et sp. nov., from the middle Oligocene of eastern Asia. Phylogenetic analyses indicate that the new species is closely related to Nimravus and Dinaelurus, and it represents a non-sabertooth ecomorph form with initial bone-cracking adaptation—a unique form among Nimravidae. An increase in body size among Nimravidae appears to have coincided with the demise of Oxyaenidae, another carnivorous clade in the Palaeogene. The initial emergence of macrocarnivorous adaptation of Carnivora by a felid-like ecomorph probably reflects competition dynamics. Nimravidae successfully occupied several ecological niches that were not exploited by Felidae, probably owing to the lack of competition within Carnivora during much of their evolutionary history. Our study underscores the role of both abiotic and biotic factors in shaping niche availability for these animals, emphasizing the need for discussions on niche change and evolution to be grounded in these considerations.

Keywords: eastern Asia, Oligocene, Taotienimravus, niche, sabertooth

  Life reconstruction of Taotienimravus songi gen. et sp. nov. in Chinese painting style.

 Artwork by Yuefeng Song.

 Mammalia Linnaeus 1758 

Carnivora Bowdich 1821 

Nimravidae Cope 1880 

Nimravinae Cope 1880 

Taotienimravus songi gen. et sp. nov. 

 

 Etymology: the generic name prefix Taotie is a fierce beast in ancient Chinese legend, referring to the large and robust dentition of the animal; the species name is in honour of the collector of the fossil specimen, Yuefeng Song, who donated the specimen to Yingliang Stone Natural History Museum and made it available for scientific research.

 Distribution and age: so far only known from the Qingshuiying Formation, Ningxia, northern China, late Early or early Late Oligocene, representing one of the youngest members of the subfamily Nimravinae. 

Qigao Jiangzuo; Georgios Lyras; Camille Grohe; Lars Werdelin ; Kecheng Niu; Dongting Huang; Shijie Li; Hao Jiang; Jiao Fu; Yang Wan; Jinyi Liu; Shi-Qi Wang and Tao Deng. 2025. A New ecomorph of Nimravidae, and the early Macrocarnivorous Niche Exploration in Carnivora. Proc Biol Sci. 292 (2059): 20251686. DOI: doi.org/10.1098/rspb.2025.1686 [26 Nov 2025]

[PaleoMammalogy • 2022] Pangurban egiae • An early Nimravid from California and the Rise of Hypercarnivorous Mammals after the middle Eocene Climatic Optimum

Pangurban egiae

Poust, Barrett & Tomiya, 2022

DOI: 10.1098/rsbl.2022.0291

  ehub-kyoto-u.com   twitter.com/SusumuTomiya

Abstract

Carnivoraforms (crown carnivorans and their closest relatives) first occupied hypercarnivorous niches near the dawn of the late Eocene, 40–37 Ma. This followed the decline or extinction of earlier carnivorous groups, Mesonychia and Oxyaenodonta, leaving carnivoraforms and hyaenodontan meat-eaters as high trophic level consumers. The pattern of this change and the relative contributions of the taxonomic groups has hitherto been unclear. We report a new genus and species of the sabretoothed mammalian carnivore family Nimravidae, Pangurban egiae, from the Eocene Pomerado Conglomerate of southern California, with strongly derived hypercarnivorous features. While geochronologically the oldest named nimravid in North America, Pangurban egiae is recovered as phylogenetically derived, with affinities to Hoplophoneus. This provides unequivocal evidence for rapid radiation and spread of nimravid carnivores across Asia and North America and constrains the timing of early divergences within the family. Pangurban egiae narrows the gap between convergent iterations of sabretoothed mammalian carnivores and demonstrates swift diversification of the hypercarnivorous nimravids during a period of global climatic instability. Furthermore, it highlights the top-to-bottom restructuring North American ecosystems underwent during the Eocene–Oligocene transition, resulting in carnivoraforms taking positions as trophic specialists for the first time, a niche they still occupy today.

Keywords: evolution, sabretooth, Hoplophoneus, Eocene–Oligocene biotic transition, Duchesnean, carnassial

 

 Systematic palaeontology

Class MAMMALIA sensu Rowe [1988]

unranked clade CARNIVORAMORPHA sensu Bryant [1996] (amended from Wyss & Flynn [1993])

unranked clade CARNIVORAFORMES Flynn, Finarelli & Spaulding [2010]

Family NIMRAVIDAE sensu Bryant [1996]

Pangurban egiae gen. et sp. nov.

  

Type locality and horizon. SDSNH Locality 4042 (Spring Canyon Site 2). Upper member of Pomerado Conglomerate, San Diego, CA, USA, here considered middle to late Duchesnean in age (ca 40–37 Ma; see electronic supplementary material, text).

Diagnosis. Anterior cutting edge of P4 expressed as sharp and distinct preparacristal blade, not reaching apex of paracone; anterior face of P4 flattened and nearly vertical giving the paracone a steep angle. Differs from: Maofelis and MA-PHQ 348 (undet. nimravid specimen housed at Muséum d'Histoire Naturelle Victor Brun, Montauban, France) in infraorbital foramen posterior to P3, double-rooted P3, P3 width to length ratio 0.4–0.65; Maofelis, MA-PHQ 348, and ‘nimravines’ of which includes barbourofelins, in reduced or absent P4 protocone, P4 metastylar blade length to paracone length ratio of 1.0–1.3, P3 crown height 48–70% that of P4; hoplophoneins (Hoplophoneus, Eusmilus and Nanosmilus) in the absence of parastyle on P4.

Etymology. The generic name is from the Old Irish, in reference to the cat in the 9th century CE poem of the same name, whose hunting is likened to the academic pursuit of truth. The species name honours the contribution of palaeontologist Naoko Egi to the study of terrestrial carnivore evolution on both sides of the northern Pacific Ocean, mirroring the nimravid distribution.

Ashley W. Poust, Paul Z. Barrett and Susumu Tomiya. 2022. An early Nimravid from California and the Rise of Hypercarnivorous Mammals after the middle Eocene Climatic Optimum. Biol. Lett.18; 20220291. DOI: 10.1098/rsbl.2022.0291

新種の化石肉食哺乳類の発見

An early nimravid from California and the rise of hypercarnivorous mammals after the Middle Eocene Climatic Optimum

  ehub-kyoto-u.com/20221013-tomiya 

 twitter.com/SusumuTomiya/status/1580411305629872128

[PaleoMammalogy • 2021] Eusmilus adelos • The Largest Hoplophonine (Carnivora: Nimravidae) and A Complex New Hypothesis of Nimravid Evolution

Eusmilus adelos

 Barrett, 2021

DOI: 10.1038/s41598-021-00521-1 

twitter.com/nimravenous 

skeletal reconstruction by Dhruv Franklin  twitter.com/DhruvFranklin

Abstract

Nimravids were the first carnivorans to evolve saberteeth, but previously portrayed as having a narrow evolutionary trajectory of increasing degrees of sabertooth specialization. Here I present a novel hypothesis about the evolution of this group, including a description of Eusmilus adelos, the largest known hoplophonine, which forces a re-evaluation of not only their relationships, but perceived paleoecology. Using a tip-dated Bayesian analysis with sophisticated evolutionary models, nimravids can now be viewed as following two paths of evolution: one led to numerous early dirk-tooth forms, including E. adelos, while the other converged on living feline morphology, tens of millions of years before its appearance in felids.

Partial skeleton of USNM 12820, Eusmilus adelos with shaded known elements. Cranial abbreviations: fr frontal, na nasal, mp mastoid process, (A) cn carnassial notch, mc main cusp of P3, pa paracone, pcc posterior cingular cusp of P3, ps parastyle; (B–D) bis brachialis insertion site, lg lateral groove of ulna, rn radial notch, sln semilunar notch, (E–G) ce capitular eminence of radius, rt radial tuberosity, (H–J) dpc delto-pectoral crest, of olecranon fossa, sc supinator crest (brachial flange), *remnants of bridge enclosing epicondylar foramen. Eusmilus adelos skeletal reconstruction by Dhruv Franklin.

Tip-dated Bayesian phylogeny of the Nimravidae, outgroups (save Tapocyon) removed. Two main clades were recovered, the Hopliphoninae and Nimravinae, the latter of which includes all barbourofelin taxa. Color gradient reflects maximum-likelihood estimation of ancestral body mass. Additional nodal values (e.g., posterior probability, divergence dates) can be found in Supplementary.

Systematic palaeontology

Carnivora 

Nimravidae 

Eusmilus 

Eusmilus adelos sp. nov.

Holotype: Smithsonian National Museum of Natural History, Washington D.C., USA (USNM) 12820: partially crushed cranium, parts of both dentaries, atlas, axis, 3rd, 5th and 7th cervical vertebrae, three lumbar vertebrae, left: scapula, distal humerus, proximal and distal ends of radius, proximal ulna (Figs. 1, 2, 3, Supplementary Figs. S1–S3).

Etymology: From the Greek adelos, for unseen, unknown, or secret. The specific epithet refers to the unclear taxonomic affiliations these specimens have had in their more than 85 year history of publication. 

Paul Zachary Barrett. 2021. The Largest Hoplophonine and A Complex New Hypothesis of Nimravid Evolution. Scientific Reports. 11, 21078. DOI: 10.1038/s41598-021-00521-1

 twitter.com/nimravenous/status/1453107573788344320

 twitter.com/DhruvFranklin/status/1453122170784256004

[PaleoMammalogy • 2020] Oriensmilus liupanensis • A New Genus and Species of Sabretooth (Carnivora: Nimravidae: Barbourofelinae) from the middle Miocene of China suggests Barbourofelines are Nimravids, not Felids

 Oriensmilus liupanensis 

Wang, White & Guan, 2020

DOI: 10.1080/14772019.2019.1691066 

 twitter.com/JournalSystPal 

Abstract

Since the early 2000s, a revival of a felid relationship for barbourofeline sabretooths has become popular due to recent discoveries of fragmentary fossils from Africa. According to this view, barbourofelines trace their common ancestor with felids through shared similarities in dental morphology going back to the early Miocene of Africa and Europe. However, whether or not such an idea is represented in the basicranial morphology, a conservative area of high importance in family-level relationships, is yet to be tested. A nearly complete skull of Oriensmilus liupanensis gen. and sp. nov. from the middle Miocene Tongxin Basin of northern China represents the most primitive known barbourofeline with an intact basicranial region, affording an opportunity to re-examine the relationship of felids and nimravines. We also present an update on East Asian records of barbourofelines. The new skull of Oriensmilus possesses a suite of characters shared with nimravines, such as the lack of an ossified (entotympanic) bullar floor, absence of an intrabullar septum, lack of a ventral promontorial process of the petrosal, presence of a small rostral entotympanic on the dorsal side of the caudal entotympanic, and a distinct caudal entry of the internal carotid artery and nerve that pierces the caudal entotympanic at the junction of the ossified and unossified caudal entotympanics. The absence of an ossified bullar floor in O. liupanensis and its presence in those from the middle Miocene of Sansan, France thus help to bracket the transition of this character, which must have happened in the early part of the middle Miocene. Spatial relationships between bullar construction and the middle ear configuration of the carotid artery in Oriensmilus strongly resemble those in nimravines but are distinctly different from felids and other basal feliforms. Despite the attractive notion that early barbourofelines arose from a Miocene ancestor that also gave rise to felids, the basicranial evidence argues against this view.

 

Keywords: Barbourofelinae, basicranium, phylogeny, Tongxin, Cenozoic, Asia

 Skull of Oriensmilus liupanensis (IVPP V25220, holotype) from Gunziling, Tongxin County in A, right lateral; and B, dorsal views.

Order Carnivora Bowdich, 1821 

Family Nimravidae Cope, 1880 

Subfamily Barbourofelinae Schultz, Schultz and Martin, 1970 

Oriensmilus gen. nov.

 Type and only species. Oriensmilus liupanensis gen. and sp. nov. 

Etymology. ‘Oriens’, Latin for rising (of the sun), commonly referring to East Asia; ‘smile’, Greek for carving knife, in allusion to the long canine tooth of barbourofelines.

Oriensmilus liupanensis sp. nov.  

1841 Sansanosmilus palmidens (Blainville); Chen & Wu 1976, 7. 

2013b Sansanosmilus sp. (Qiu et al.); Wang et al. 2016, 798, fig. 4G.

Etymology. Refers to the Liupan Mountains (Liupan Shan); the Tongxin Basin is located at the northern foothills of the Liupan Mountains.

Type locality and horizon. IVPP V25220 is from Gunziling, about 10–12 km south of the small village Dingjia’ergou (Qiu et al. 2013b, p. 59) in the Tongxin Basin, Tongxin County, Ningxia Hui Autonomous Region; upper part of Zhang’enbao Formation (Fig. 1).

 

 

Xiaoming Wang, Stuart C. White and Jian Guan. 2020. A New Genus and Species of Sabretooth, Oriensmilus liupanensis (Barbourofelinae, Nimravidae, Carnivora), from the middle Miocene of China suggests Barbourofelines are Nimravids, not Felids. Journal of Systematic Palaeontology. 18, 9. DOI: 10.1080/14772019.2019.1691066  

twitter.com/JournalSystPal/status/1215671887185043456