[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]

[Paleontology • 2025] Ueloca colemanorum • A New Leatherback Marine Turtle from the lower Oligocene of North America and A Phylogenetic Nomenclature for Dermochelyidae

Ueloca colemanorum 

 Gentry, Burns, Ebersole, Gregson, Martinez & Parham, 2025 

 DOI: doi.org/10.18476/pale.v18.a6

Abstract

The modern leatherback sea turtle Dermochelys coriacea possesses a unique, flexible mosaic carapace adapted for deep diving. The evolutionary origins of this structure remain poorly understood because of the fragmentary nature of the fossil record. Here we describe Ueloca colemanorum n. gen. n. sp., a novel ridgeless leatherback turtle from the lower Oligocene Glendon Limestone of Alabama, USA. This specimen (MSC 49490) represents one of the most complete fossil leatherback carapaces known and provides new insight into dermochelyid diversity and shell evolution. The carapace is composed of parallel rows of enlarged ossicles interspersed with smaller ossicles arranged in distinctive floriform patterns. Histological analysis reveals a cancellous core with an external cortex but no basal cortex, a condition also observed in Dermochelys coriacea. Phylogenetic analysis places Ueloca within a clade of ridgeless leatherbacks (Uelocini), which diverged from ridge-bearing Dermochelyini in the Eocene. Our revised phylogeny suggests that Uelocini and Dermochelyini represent the two main lineages of dermochelyines, both characterized by mosaic carapaces that undergo parallel morphological trends. These findings clarify the deep history of leatherback shell evolution and emphasize the need for additional well-preserved fossils to further refine dermochelyid systematics.

KEYWORDS: Dermochelys, Glendon Limestone Member, Gulf Coastal Plain, North America

Ueloca colemanorum n. gen. n. sp. from the lower Oligocene of Alabama, USA.
A, B – MSC 49490, holotype, carapace in dorsal view. Scale bar = 10 cm.

Dermochelyinae Weems, 1988

Uelocini new clade

Ueloca new genus

 

Etymology: The generic name, Ueloca (pronounced Wee-low-juh), is a Mvskoke (Creek) name derived from the Mvskoke words “Uewv” for water and “Loca” for turtle. This name honors the indigenous people of southern Alabama and serves as recognition of the contributions of Poarch Creek Indian tribal members to this project.

 Ueloca colemanorum n. gen. n. sp. 

 

Ueloca colemanorum new species

  

Etymology: The species name, colemanorum, honors the Coleman family (Adrienne, Adam, Talah, and Corey) of Mobile, Alabama, who discovered MSC 49490 and then dedicated an extraordinary amount of time, energy, and resources to its recovery.

Holotype: MSC 49490.

Occurrence: Site AMo-10, Monroe County, AL, USA. Lower Oligocene (Rupelian) Glendon Limestone Member of the Byram Formation (NP 22, 33–32 Ma).

Diagnosis: Ueloca colemanorum can be differentiated from most dermochelyids by an absence of carapacial ridges and by having a carapace with parallel, anteroposteriorly oriented rows of enlarged ossicles and clusters of ossicles arranged in floriform or ‘sunflower’ patterns. U. colemanorum. can be distinguished from other ridgeless dermochelyids with floriform ossicle patterns (Ca. rupeliensis and N. peruvianus) by having unsculptured ossicles that regularly exceed 4 cm in length, that are not associated with either floriform patterns or rows of enlarged ossicles, lacking deeply interdigitating ossicle sutures, and having central ossicles of floriform patterns which are only moderately scalloped.

Andrew D. Gentry, Michael E. Burns, Jun A. Ebersole, Kimberly A. Gregson, Emma C. Martinez and James F. Parham. 2025. A New Leatherback Marine Turtle from the lower Oligocene of North America and A Phylogenetic Nomenclature for Dermochelyidae. Palaeodiversity. 18(1):127-149. DOI: doi.org/10.18476/pale.v18.a6 [12 September 2025]

  facebook.com/PoarchCreekIndians/posts/1178500574313360

[PaleoMammalogy • 2025] Janjucetus dullardi • An Immature Toothed Mysticete from the Oligocene of Australia and insights into mammalodontid (Mysticeti: Mammalodontidae) Morphology, Systematics, and Ontogeny

 

Janjucetus dullardi 

Duncan, Rule, Park, Evans, Adams & Fitzgerald, 2025

DOI: doi.org/10.1093/zoolinnean/zlaf090 

  x.com/Inxcetus

Abstract

Mammalodontids are a clade of toothed mysticetes known only from the Chattian of south-eastern Australia and New Zealand. Despite three named species (Janjucetus hunderi, Mammalodon colliveri, and Mammalodon hakataramea), the majority of mammalodontid material, largely represented by isolated teeth and ear bones found within the Torquay Basin (Victoria, Australia), remains undescribed. Here we describe a new species of mammalodontid, Janjucetus dullardi sp. nov., from the Jan Juc Marl. The holotype was found stratigraphically lower than M. colliveri and has morphology consistent with an immature stage of growth, plus near-unworn dental morphology. We identify a correlation between occipital condyle breadth and bizygomatic width and propose equations that permit us to estimate bizygomatic width and, subsequently, a body size estimate similar to the smallest known toothed mysticetes of ∼2.05–2.18 m. Phylogenetic analysis recovers J. dullardi as sister to J. hunderi within a monophyletic mammalodontid clade in all analyses. It also provides support for Mammalodontidae within Mysticeti, sister to an Aetiocetidae + Chaeomysticeti clade. Finally, revised diagnoses of Mammalodon and Janjucetus incorporating newly recogniszed tympanic and periotic characters permit the identification of isolated ear bones and inference of ontogenetic variation within Janjucetus.

Australia, Cetacea, Janjucetus, Mammalodon, Mammalodontidae, Mysticeti, Oligocene, ontogeny, phylogeny

Artist’s reconstruction of the complete skull of Janjucetus dullardi.
Parts preserved in the fossil are white and light grey.

 Art by Ruairidh Duncan

Janjucetus dullardi sp. nov. 

Etymology: The species name dullardi honours Mr Ross Dullard, who discovered the holotype.

Type locality, horizon, and age: The holotype of Janjucetus dullardi (NMV P256471) was discovered near the town of Jan Juc in the lowest beds of the exposed onshore Jan Juc Marl at Half Moon Bay, southwest of Bird Rock (Fig. 2) at approximately 38°21′03″S, 144°18′02″E (precise locality details are available on request). The lithology of this cliff face describes a neritic, inner mid-shelf environment, which coarsens upwards, and with relatively low abundance of infauna (Li et al. 1999, McLaren et al. 2009). The type of J. dullardi was found near the base of this outcrop, exposed beneath a wave-eroded overhang, slightly above the level of the tidal beach sands (Fig. 1). The lithology of this horizon [unit 1 and 2 of Reeckmann (1979)] is one of a silty, sandy grey marl, interspersed with bedding planes of coarse silts to fine sandstones and rich in glauconite. A horizon ∼3 m above the fossil-producing layer was aged to 24.67 Mya using strontium isotope ratios (Korasidis et al. 2018). The top of the Bells Headland outcrop, interpreted as ∼2 m stratigraphically lower than the base of the Bird Rock outcrop, was aged to 26.05 Mya at a point correlated to ∼2.5 m below the horizon containing NMV P256471 using the same methodology (Korasidis et al. 2018). We therefore give an estimated age of this specimen of between 24.67 and 26.05 Mya (middle Chattian).

Diagnosis: We interpret J. dullardi as a mammalodontid on the basis of: the presence of an involucral concavity on the medial surface of the tympanic bulla ventral to the involucral ridge; a dorsomedially extended and anteroposteriorly wide crista transversa, which reaches to the level of the rim of the internal acoustic meatus medially (also seen in Salishicetus and Coronodon); and the presence of apicobasal ridges on both the buccal and lingual surfaces of the tooth crowns (also seen in Morawanocetus, ­Coronodon, and Llanocetus).

This specimen shares the following features with J. hunderi to the exclusion of Mammalodon: an obliquely truncated rather than squared anterior margin of the tympanic bulla; an inner posterior prominence of the tympanic bulla mediolaterally broader than the outer posterior prominence at the widest point of the bulla; periotic body and posterior process greatly exceed the posterior margin of the fenestra rotunda; anteroposterior and dorsoventral diameters of the anterior process of the periotic are subequal to one another; and the mandibular posterior postcanine teeth lack a distal accessory shelf near the base of the crown.

...

Janjucetus dullardi calf and mother swimming through the shallow seas, 25 million years ago.

Art by Ruairidh Duncan

 

Ruairidh J Duncan, James P Rule, Travis Park, Alistair R Evans, Justin W Adams and Erich M G Fitzgerald. 2025. An Immature Toothed Mysticete from the Oligocene of Australia and insights into mammalodontid (Cetacea: Mysticeti) Morphology, Systematics, and Ontogeny. Zoological Journal of the Linnean Society. 204(4); zlaf090. DOI: doi.org/10.1093/zoolinnean/zlaf090 [12 August 2025] 

  x.com/Inxcetus/status/1955406875228508362

https://theconversation.com/a-cornucopia-of-tiny-bizarre-whales-used-to-live-in-australian-waters-heres-one-of-them-262806

[PaleoMammalogy • 2025] Cranial Anatomy of the hypercarnivore Bastetodon syrtos gen. nov. (Hyaenodonta: Hyainailourinae) and A Reevaluation of Pterodon in Africa

  

Bastetodon syrtos (Holroyd, 1999)
Bastetodon gen. nov.

Al-Ashqar, Borths, El-Desouky,  Heritage, Abed, Seiffert, El-Sayed & Sallam, 2025

DOI: doi.org/10.1080/02724634.2024.2442472

 x.com/HeshamSallam

artwork by Ahmed Morsi

ABSTRACT

During the Paleogene in Afro-Arabia, most terrestrial mammalian carnivores belonged to Hyaenodonta, an extinct lineage bearing a pair of carnassials between each set of molars. The Fayum Depression of Egypt preserves multiple lineages of hyaenodonts across the Eocene–Oligocene boundary. Here, we describe one of the most complete hyaenodont crania ever recovered from the lower Oligocene of the Fayum (Jebel Qatrani Formation, Quarry I, ∼30 Ma). The cranium is about the size of a hyena’s and preserves the complete upper tooth row. The long, shearing metastyle and reduced and mesially shifted protocones indicate a hypercarnivorous diet, and robust zygomatic arches suggest strong chewing muscles. Based on dental comparisons, we refer the cranium to Bastetodon syrtos (previously “Pterodon” syrtos). Bastetodon syrtos has three premolars and two molars—a reduced dental formula compared with other Fayum hyainailourines such as Akhnatenavus and European hyainailourines such as Pterodon. The cranium preserves the clover-shaped lambdoidal crest and long pharyngeal tube that unites Hyainailouroidea (Apterodontinae, Teratodontinae, and Hyainailourinae). The new Fayum cranium allows us to reevaluate the genus Pterodon and explore characters that distinguish Afro-Arabian and Eurasian species placed in this genus. Our phylogenetic analysis recovers a paraphyletic Pterodon, with B. syrtos as the sister taxon of Falcatodon schlosseri. We erect Sekhmetops to describe the large Fayum hyainailourine species S. phiomensis and S. africanus. This effort clarifies the biogeographic history of the clade that includes Pterodon, revealing multiple Tethys Seaway dispersals during the Paleogene followed by endemic radiations in Eurasia and Afro-Arabia.

Genus  Bastetodon gen. nov.

Pterodon syrtos Holroyd, 1999:8, fig. 4 (original description).

 

Etymology—Bastetodon, from “Bastet,” one transliteration of the name of the ancient Egyptian, cat-headed goddess of protection, pleasure, and bringer of good health. She was also associated with the lion-headed goddess Sekhmet. And ancient Greek “odon” meaning tooth. Literally, “Teeth like the cat-headed goddess.”

 

 Genus SEKHMETOPS gen. nov.

Type Species—Sekhmetops africanus (Andrews, 1904)

Included Species—Sekhmetops phiomensis (Osborn, 1909)

Etymology—From Sekhmet, the wrathful lion-headed goddess of Ancient Egypt associated with war and pestilence. And “ops” meaning “face” in ancient Greek. Literally, “Having the face of the lion-headed goddess.”

Shorouq F. Al-Ashqar, Matthew Borths, Heba El-Desouky, Steven Heritage, Mohamed Abed, Erik R. Seiffert, Sanaa El-Sayed and Hesham M. Sallam. 2025. Cranial Anatomy of the hypercarnivore Bastetodon syrtos gen. nov. (Hyaenodonta, Hyainailourinae) and A Reevaluation of Pterodon in Africa. Journal of Vertebrate Paleontology. e2442472. DOI: doi.org/10.1080/02724634.2024.2442472

 x.com/HeshamSallam/status/1891405486022422752

Notably, this study refutes the monophyly of “Pterodon.” Based on the morphological features and the phylogenetic analyses conducted within this study, we suggest that Pterodon has never been found in Afro-Arabia. “Pterodon” syrtos is now placed in Bastetodon syrtos and “Pterodon” africanus and “Pterodon” phiomensis are placed in the new genus Sekhmetops. Under this taxonomic scheme, Pterodon is now restricted to the Eocene of Europe.

[PaleoMammalogy • 2024] Badjcinus timfaulkneri, Nimbacinus peterbridgei & Ngamalacinus nigelmarveni • Three New thylacinids (Marsupialia: Thylacinidae) from late Oligocene Deposits of the Riversleigh World Heritage Area, northwestern Queensland, Australia

Nimbacinus peterbridgei (top right) and Ngamalacinus nigelmarveni (bottom right)
interacting with Kuterintja ngama (top left) and Gumardee springae (bottom left). 

Churchill, Archer & Hand, 2024

DOI: 10.1080/02724634.2024.2384595  

Illustration by Peter Schouten.

ABSTRACT

New thylacinid species of Badjcinus, Nimbacinus, and Ngamalacinus are described from upper Oligocene deposits of the Riversleigh World Heritage Area, northwestern Queensland. Badjcinus timfaulkneri, Nimbacinus peterbridgei, and Ngamalacinus nigelmarveni are among the oldest thylacinids yet known and indicate an earlier diversification of the family than previously understood. Maximum parsimony analysis supports a sister group relationship between Ng. nigelmarveni and Ng. timmulvaneyi, but the relationships of the two other new taxa are unresolved. Bayesian dated total evidence analysis using morphological and molecular data supports the generic assignment of B. timfaulkneri and Ng. nigelmarveni but not that of Ni. peterbridgei. Both phylogenies herein support a taxonomic reassignment of Thylacinus macknessi to the genus Wabulacinus, a conclusion also supported by the results of previous studies. Body mass estimates based on molar size regressions indicate body sizes ranging from 3.7 kg to 11.4 kg for the new thylacinid species. Badjcinus timfaulkneri exhibits an extremely deep jaw compared with other thylacinids, with mandibular bending strength analysis suggesting that it was a highly durophagous carnivore much like the modern dasyurid Sarcophilus harrisii. This analysis also suggests Ni. peterbridgei had a dentary more similar in shape to that of plesiomorphic thylacinid faunivores such as Ni. dicksoni and T. cynocephalus suggesting that it had a relatively more generalist faunivorous diet. The molars of Ng. nigelmarveni suggest they were better suited for longitudinal slicing than the molars of B. timfaulkneri and Ni. peterbridgei, indicating a more hypercarnivorous diet compared with that of those species.

SYSTEMATIC PALEONTOLOGY

MAMMALIA Linnaeus, 1758

MARSUPIALIA Illiger, 1811 sensu Beck et al., 2014

DASYUROMORPHIA Gill, 1872 sensu Kealy & Beck 2017

THYLACINIDAE Bonaparte, 1838

BADJCINUS Muirhead & Wroe, 1998

BADJCINUS TIMFAULKNERI sp. nov. 

Species Diagnosis—Badjcinus timfaulkneri differs from all other known thylacinids in possessing the following combination of lower dental features: large diastemas between both p1–p2 and p2–p3; broad talonids on all lower molars; m1 paraconid and paracristid highly reduced; m1 metaconid absent; m2–4 metaconids reduced; m4 larger than m3; three cusps on m4 talonid; two mental foramina below midpoints of m1 and m2. Badjcinus timfaulkneri differs from B. turnbulli in the following lower dental features: p1 less reduced in size relative to p2 and p3; larger diastemata between p1–p2 and p2–p3; anterior cingulid absent on m1; talonids broader on all molars.

Etymology—The species name timfaulkneri honors Tim Faulkner, head of conservation at the Australian Reptile Park and founder of The Devil Ark, for his life’s dedication to the conservation of dasyuromorphian marsupials and of Australian wildlife in general.

Holotype—QM F61721 (Fig. 1) is a near complete right dentary of an adult individual retaining p2 and m1–4, with alveoli for p1 and p3. Dental measurements are given in Table 1.

Nimbacinus peterbridgei (top right) and Ngamalacinus nigelmarveni (bottom right) interacting with Kuterintja ngama (top left) and Gumardee springae (bottom left).

 Illustration by Peter Schouten.

NIMBACINUS Muirhead & Archer, 1989

NIMBACINUS PETERBRIDGEI sp. nov.

Species Diagnosis—Nimbacinus peterbridgei differs from the larger Ni. dicksoni in the following combination of lower dental features: the premolars and molars markedly less robust overall; the anterior cingulid on m2–4 extends beyond the buccal extremity of the trigonid; the cristid obliqua less transverse; the m4 trigonid angle is smaller; the m4 hypoconulid is large and is situated at the transverse midpoint of the talonid, rather than being lingually proximal to the entoconid; the hypoconid and entoconid are less reduced on m4.

Etymology—The species name peterbridgei honors mineralogist Peter Bridge OAM who has dedicated his life to bringing the past of Australia’s natural and cultural history into the present by supporting our paleontological field expeditions and publishing as well as authoring via Hesperian Press hundreds of books about Australia’s extraordinary human and natural history.

Holotype—QM F61723 (Fig. 3) is a right dentary preserving p1, p3, m2–4 and alveoli for p2 and m1. Dental measurements are shown in Table 2.

NGAMALACINUS Muirhead, 1997

NGAMALACINUS NIGELMARVENI Sp. Nov.

 

Species Diagnosis—Ngamalacinus nigelmarveni differs from Ng. timmulvaneyi in the following lower dental features; trigonids broader; trigonid angles smaller; entoconids and hypoconulids not closely twinned on m2–3; m3 entoconid smaller than that cusp in m2; metacristid longer on m2; m4 talonid broader; m4 posterior cristid longer and more transverse, with a distinct postmetacristid valley near the junction of the posthypocristid and prehypoconulecristid; m4 hypoconulid larger; m4 posterior cingulid longer and contacts the base of the postmetacristid valley.

Etymology—The species name nigelmarveni honors British television presenter and naturalist Nigel Marven for his lifetime dedication to inspiring young paleontologists through his unique and daring style of presenting documentaries on ancient life.

 

Timothy J. Churchill, Michael Archer and Suzanne J. Hand. 2024. Three New thylacinids (Marsupialia, Thylacinidae) from late Oligocene Deposits of the Riversleigh World Heritage Area, northwestern Queensland. Journal of Vertebrate Paleontology. e2384595. DOI: doi.org/10.1080/02724634.2024.2384595  

  www.unsw.edu.au/newsroom/news/2024/09/three-new-ancestors-tasmanian-tigers

[PaleoOrnithology • 2024] Pakudyptes hakataramea • A New tiny fossil Penguin from the Late Oligocene of New Zealand and the Morphofunctional Transition of the Penguin Wing

Pakudyptes hakataramea 

 Ando, Robinson, Loch, Nakahara, Hayashi, Richards & Fordyce, 2024

DOI: 10.1080/03036758.2024.2362283 

   x.com/SHOWJI0329

 

ABSTRACT

The Late Oligocene is a period of high penguin diversity, following major changes in the marine environment at the Eocene/Oligocene boundary and prior to the emergence of crown penguins in the Miocene. Historically, a large morphological gap existed between the most crownward Platydyptes among the Oligocene penguins from New Zealand and the Early Miocene stem penguins such as Palaeospheniscus from South America. Here we describe a new species that contributes to filling this gap. Pakudyptes hakataramea gen. et sp. nov. is the earliest tiny penguin, overlapping in size with the little penguin Eudyptula minor. Its distinctive combination of a well-developed proximal end of the humerus and an archaic elbow joint provides clues to the evolution of penguin wings. Phylogenetic analysis indicates that penguin wings evolved rapidly from the Late Oligocene to the Early Miocene, together with the acquisition of morphofunctional and hydrodynamical characteristics that enable the excellent swimming ability of modern penguins. As an indicator of aquatic adaptation, bone microanatomy shows a comparable structure to that of Eudyptula. The appearance of the smallest body size and the evolution of modern wings may have led to the ecological diversity of modern penguins, which confirms the importance of Zealandia in penguin evolution.

KEYWORDS: Smallest fossil penguin, Latest Oligocene, New Zealand, phylogeny, evolution of wing

 Pakudyptes hakataramea gen. et sp. nov.

  

 

 

Tatsuro Ando, Jeffrey Robinson, Carolina Loch, Tamon Nakahara, Shoji Hayashi, Marcus D. Richards and Robert Ewan Fordyce. 2024. A New tiny fossil Penguin from the Late Oligocene of New Zealand and the Morphofunctional Transition of the Penguin Wing. Journal of the Royal Society of New Zealand. DOI: doi.org/10.1080/03036758.2024.2362283  

[Special issue: Fossil vertebrates from southern Zealandia]

  x.com/SHOWJI0329/status/1818706038839033891

[Paleontology • 2024] Hibernophis breithaupti • Morphology and Systematics of A New fossil Snake from the early Rupelian (Oligocene) White River Formation, Wyoming

 

 Hibernophis breithaupti

 Croghan, Palci, Onary, Lee & Caldwell, 2024

DOI: 10.1093/zoolinnean/zlae073 

 x.com/Michael_S_Y_Lee

 

Abstract

Extinct snake taxa are recognized primarily from isolated vertebrae. A new specimen from the early Oligocene of Wyoming provides a rare opportunity to examine four nearly complete and articulated fossil snakes. Informally assigned previously to the ‘erycine’ vertebral form taxa Ogmophis and Calamagras, a detailed comparison reveals that this fossil snake exhibits vertebral differences from both taxa and is, furthermore, a new taxon, Hibernophis breithaupti gen. et sp. nov., based on a combination of apomorphies such as absence of basal tubera, low subrectangular prootic, low parasphenoid wings obscuring the anterior opening of the Vidian canal, and foramen for the mandibular branch of the trigeminal nerve posteriorly displaced inside the adductor fossa of the compound. Parsimony and Bayesian phylogenetic analysis of combined morphological and molecular data from a broad selection of snakes places Hibernophis breithaupti as sister taxon to all other booids, distant from both Old and New World ‘erycines’. However, an alternative position close to New World ‘erycines’ and ungaliophiines cannot be rejected.

Booidea, Erycidae, Erycinae, evolution, computed tomography, phylogeny

Hibernophis breithaupti gen. et sp. nov.

Jasmine A. Croghan, Alessandro Palci, Silvio Onary, Michael S. Y. Lee and Michael W. Caldwell. 2024. Morphology and Systematics of A New fossil Snake from the early Rupelian (Oligocene) White River Formation, Wyoming. Zoological Journal of the Linnean Society, zlae073. DOI: doi.org/10.1093/zoolinnean/zlae073

  x.com/Michael_S_Y_Lee/status/1803952638398206000

https://www.instagram.com/p/C8dT4PpShmP

 phys.org/news/2024-07-fossil-snake-species-insight-reptile.html

[PaleoMammalogy • 2024] Aureia rerehua • A New platanistoid Dolphin (Cetacea: Odontoceti) from the Oligocene of New Zealand with a unique feeding method

 

Aureia rerehua

Meekin, Fordyce & Coste, 2024

DOI: 10.1080/03036758.2024.2314505

  Researchgate.net/publication/378366471

 

ABSTRACT

Pre-Miocene, stem odontocetes are known for their procumbent incisors and their function has been the subject of much speculation. Notable among these were Waipatia and several related taxa from New Zealand. Though some studies hypothesise the function of these teeth was for thrusting, the here described Aureia rerehua has unique teeth which might have formed a cage around small fish. These teeth, along with a weak vertex, flexible neck, and the smallest size among its relatives would make it a capable hunter in shallow waters. The addition of A. rerehua along with other taxa to phylogenetic analyses show three broad groups within taxa related to Waipatia and Otekaikea based on the divergence of the function of their teeth and the possible feeding strategies employed to catch prey.

KEYWORDS: Platanistoid, dental splay, waipatiid, Waipatiidae, Waitaki Valley

  

 A, The skull of Aureia rerehua in dorsal. B, Ventral, C, Left lateral view.
Note the splay of the teeth and facial topography.

Systematic palaeontology

Cetacea (Brisson, 1762)

Odontoceti (Flower, 1867)

Aureia rerehua gen. et sp. nov.

Etymology: The generic name derives from Māori aurei, ‘cloak pin’, referring to the shape of the teeth. The specific name, rerehua, means ‘beautiful’, referring to its well-preserved face.

Diagnosis: 

A. rerehua has features common in other stem odontocetes and some platanistoids; a subcircular fossa in the periotic fossa sensu de Muizon (1987), ventrally deflected anterior processes on the periotics, anterior spines on the tympanic bullae, distinct premaxillary clefts, and well developed antorbital notches (de Muizon, 1987; Geisler and Sanders, 2003; Geisler et al. 2011, 2012; Murakami et al. 2012a, 2012b; Tanaka and Fordyce 2014; Tanaka and Fordyce 2015b; Gaetán et al. 2018). A. rerehua is most like Otekaikea and Waipatia, with an attenuated rostrum, procumbent incisors, fossa for the articular rim of the periotic, and shallow fossae for the sternomastoid muscle (Moore, 1968; de Muizon, 1987; Tanaka and Fordyce, 2015b, 2014, 2017).

A. rerehua has unique basioccipital crests with posteroventral projections, a rectangular nuchal crest, flat ventral surfaces on the posterior process of the periotic, laterally splayed teeth, and a process on the subtemporal crest. Waipatiid-like odontocetes have developed vertices. The vertex of A. rerehua is less pronounced than W. maerewhenua or Otekaikea, shown in Figure 1C, possessing a flatter face like Papahu taitapu (Fordyce, 1994; Aguirre-Fernández and Fordyce, 2014; Tanaka and Fordyce 2014, 2015b). The posterior skull is straighter and steeper than that of other waipatiid-like odontocetes, making the lateral profile of the skull triangular.

  The teeth of Aureia rerehua.
 A series of the best-preserved teeth A are shown along with a section of in situ teeth preserved in the left mandible B.

Conclusion: 

OU22553 is the holotypes for a new species, A. rerehua, closely related to Otekaikea. It differs from other related odontocetes by its weak vertex, laterally splayed and recurved teeth, rectangular nuchal crest, and posterior flange on the basioccipital processes. Its widely splayed teeth are hypothesised to have clasped rather than strike fish. The unique dentition, small size, limited sense of smell, and dorsoventrally shallow skull illustrate a small dolphin foraging along shallow waters where speed and mobility are essential.

Shane Meekin, R. Ewan Fordyce and Amber Coste. 2024. Aureia rerehua, A New platanistoid Dolphin from the Oligocene of New Zealand with a unique feeding method. Journal of the Royal Society of New Zealand. DOI: 10.1080/03036758.2024.2314505

[Special issue: Fossil vertebrates from southern Zealandia]

  Researchgate.net/publication/378366471_Aureia_rerehua_a_new_platanistoid_dolphin_from_the_Oligocene_of_New_Zealand

[Paleontology • 2023] Giant Baleen Whales emerged from A Cold southern Cradle

Chaeomysticete mandible fragments NMV P218462 (Museums Victoria) from the Aquitanian–Burdigalian of South Australia.

in Rule, Duncan, Marx, Pollock, Evans & Fitzgerald, 2023.

 DOI: 10.1098/rspb.2023.2177

 twitter.com/Palaeo_JRule

Abstract

Baleen whales (mysticetes) include the largest animals on the Earth. How they achieved such gigantic sizes remains debated, with previous research focusing primarily on when mysticetes became large, rather than where. Here, we describe an edentulous baleen whale fossil (21.12–16.39 mega annum (Ma)) from South Australia. With an estimated body length of 9 m, it is the largest mysticete from the Early Miocene. Analysing body size through time shows that ancient baleen whales from the Southern Hemisphere were larger than their northern counterparts. This pattern seemingly persists for much of the Cenozoic, even though southern specimens contribute only 19% to the global mysticete fossil record. Our findings contrast with previous ideas of a single abrupt shift towards larger size during the Plio-Pleistocene, which we here interpret as a glacially driven Northern Hemisphere phenomenon. Our results highlight the importance of incorporating Southern Hemisphere fossils into macroevolutionary patterns, especially in light of the high productivity of Southern Ocean environments.

Keywords: Mysticeti, Chaeomysticeti, Southern Hemisphere, body size, gigantism

Systematic palaeontology

Cetacea Brisson 1762

Neoceti Fordyce & Muizon 2001

Mysticeti Gray 1864

Chaeomysticeti Mitchell 1989

Chaeomysticeti gen. et sp. indet.

Referred specimen. NMV P218462, symphyseal regions of both mandibles, plus fragments of the left premaxilla and maxilla.

Locality and horizon. NMV P218462 was found by F.A. Cudmore (on 15 February 1921) eroding from limestone cliffs on the east bank of the Murray River, opposite Wongulla, about 5 km south of Devon Downs, South Australia. ...

 

Conclusion: 

Baleen whales first evolved large body size in the Southern Hemisphere, perhaps facilitated by the onset of the ACC and high seasonal productivity in the Southern Ocean. Previous suggestions of an abrupt global Plio-Pleistocene shift towards mysticete gigantism are hampered by a strong collection bias against austral localities that obscures more gradual and regional trends. Medium-large mysticetes may have helped to engineer ocean ecosystems, albeit in a comparatively limited fashion, since the beginning of the Neogene. Further exploration of the Southern Hemisphere is crucial to constructing a truly global picture of the nature, timing and impacts of whale evolution.

James P. Rule, Ruairidh J. Duncan, Felix G. Marx, Tahlia I. Pollock, Alistair R. Evans† and Erich M.G. Fitzgerald. 2023. Giant Baleen Whales emerged from A Cold southern Cradle. Proc. R. Soc. B. 290: 20232177. DOI: 10.1098/rspb.2023.2177

 twitter.com/Palaeo_JRule/status/1737286061276242142

[PaleoMammalogy • 2023] Lumakoala blackae • A probable Koala (Diprotodontia: ?Phascolarctidae) from the Oligocene of central Australia provides insights into early diprotodontian Evolution

Lumakoala blackae

Crichton, Beck, Couzens, Worthy, Camens & Prideaux, 2023

  

DOI: 10.1038/s41598-023-41471-0

Abstract

Diprotodontians are the morphologically and ecologically most diverse order of marsupials. However, an approximately 30-million-year gap in the Australian terrestrial vertebrate fossil record means that the first half of diprotodontian evolution is unknown. Fossil taxa from immediately either side of this gap are therefore critical for reconstructing the early evolution of the order. Here we report the likely oldest-known koala relatives (Phascolarctidae), from the late Oligocene Pwerte Marnte Marnte Local Fauna (central Australia). These include coeval species of Madakoala and Nimiokoala, as well as a new probable koala (?Phascolarctidae). The new taxon, Lumakoala blackae gen. et sp. nov., was comparable in size to the smallest-known phascolarctids, with body-mass estimates of 2.2–2.6 kg. Its bunoselenodont upper molars retain the primitive metatherian condition of a continuous centrocrista, and distinct stylar cusps B and D which lacked occlusion with the hypoconid. This structural arrangement: (1) suggests a morphocline within Phascolarctidae from bunoselenodonty to selenodonty; and (2) better clarifies the evolutionary transitions between molar morphologies within Vombatomorphia. We hypothesize that the molar form of Lumakoala blackae approximates the ancestral condition of the suborder Vombatiformes. Furthermore, it provides a plausible link between diprotodontians and the putative polydolopimorphians Chulpasia jimthorselli and Thylacotinga bartholomaii from the early Eocene Tingamarra Local Fauna (eastern Australia), which we infer as having molar morphologies consistent with stem diprotodontians.

Lumakoala blackae gen. et sp. nov. upper molars. Left M 2? or 3 (Holotype, NTM P12012):

Systematic palaeontology

Infraclass Marsupialia Illiger, 1811

Order Diprotodontia Owen, 1877

Suborder Vombatiformes Woodburne, 1984

Infraorder ?Phascolarctomorphia Aplin & Archer, 1987

Family ?Phascolarctidae Owen, 1839

Lumakoala blackae gen. et sp. nov.

Genus Etymology. Luma is Latin for ‘thorn’, in reference to the morphology of stylar cusps B and D, and their distinction from the postparacrista and premetacrista, respectively. The gender of the genus is feminine.

Species Etymology. Named for Karen Black, whose research has greatly extended our understanding of fossil phascolarctids and other vombatiforms.

 

Specific Diagnosis. A new species that appears most similar in upper molar morphology to members of the Phascolarctidae, with: a deep, U-shaped longitudinal valley between the primary buccal and lingual cusps, rather than being shallow and V-shaped as in selenodont vombatomorphians; and a paraconule on M1 (Fig. 3a–h).

...

 

Arthur I. Crichton, Robin M. D. Beck, Aidan M. C. Couzens, Trevor H. Worthy, Aaron B. Camens and Gavin J. Prideaux. 2023. A probable Koala from the Oligocene of central Australia provides insights into early diprotodontian Evolution. Scientific Reports. 13: 14521. DOI: 10.1038/s41598-023-41471-0