[Paleontology • 2025] Direct Evidence of Trophic Interaction between a crocodyliform and a large terror bird in the Middle Miocene of La Venta, Colombia

 a caimanine alligatorid (Purussaurus neivensis) preying/scavenging on a large phorusrhacid bird.
 

in Link, Moreno-Bernal, Degrange, Cooke, ... et Salas-Gismondi, 2025.

DOI: doi.org/10.1098/rsbl.2025.0113

Illustrations by Julian Bayona Becerra. 

Abstract

Direct evidence of predation and other trophic relationships provide valuable information about trophic interactions between species in palaeo-communities. Data on ecological interactions amongst extant apex predators open a unique opportunity to better understand how sympatric apex predators coexisted or interacted with each other in the past. Here, we describe direct evidence of a predation or scavenging event in which we hypothesize that a medium-sized caiman (possibly Purussaurus neivensis) consumed (either through scavenging or through direct predation) a large terror bird. The distal part of a left tibiotarsus from a phorusrhacid had four pits inflicted on the cortical bone, and no signs of healing, suggesting it did not survive this trophic event. This record contributes to our current understanding of prey consumed by P. neivensis in the wetlands of the Pebas System of South America and indicates that large phorusrhacids might have had higher predation risk than previously expected. This study provides evidence of a trophic relation between apex predators and the complexity of trophic interactions in the diverse vertebrate palaeo-community of La Venta in the Middle Miocene of northern South America.

Keywords: apex predators, Phorusrhacidae, Purussaurus, superpredation, taphonomy, Caimaninae, scavenging

 

(a) Superimposed 3D models of MT−0200 and a skull of extant black caiman (Melanosuchus niger UF-Herp-53600). Both models at the same scale, the M. niger model is archived on Morphosource (https://doi.org/10.17602/M2/M359353). Total length estimated for the specimen of M. niger is 4.84 meters and is used here as an analogy to a medium sized Purussaurus (skull or mandible not available) [49]. Scale bar is 50 mm. (b) Detail of the superimposed model, showing the close match between the teeth of UF-Herp-53600 and the tooth marks on MT-0200. Scale bar is 50 mm.
(c) Artistic representation of a caimanine alligatorid (Purussaurus neivensis) preying on a large phorusrhacid bird. (d) Artistic representation of a caimanine alligatorid (Purussaurus neivensis) scavenging on a large phorusrhacid bird. Illustrations by Julian Bayona Becerra.  

 

Andres Link, Jorge Wilson Moreno-Bernal, Federico Javier Degrange, Siobhan B. Cooke, Luis Gonzalo Ortiz-Pabon, Cesar Augusto Perdomo-Rojas and Rodolfo Salas-Gismondi. 2025. Direct Evidence of Trophic Interaction between a crocodyliform and a large terror bird in the Middle Miocene of La Venta, Colombia. Biol. Lett. 21; 20250113. DOI: doi.org/10.1098/rsbl.2025.0113 [23 July 2025]

[PaleoOrnithology • 2025] DNA and Spores from Coprolites reveal that Colourful Truffle-like Fungi endemic to New Zealand were consumed by extinct Moa Megalapteryx didinus (Dinornithiformes)

 

upland moa Megalapteryx didinus (Owen, 1883)

(c) Gallacea scleroderma*, 

(d) Gallacea sp. ‘Nelson Lakes’*, 

(e) Rossbeevera pachydermis*, 

(f) Russula macrocystidiata*,

in Boast, Wood, Cooper, Bolstridge, Perry et Wilmshurst, 2025. 

DOI: doi.org/10.1098/rsbl.2024.0440  

 

Abstract

Mycovores (animals that consume fungi) are important for fungal spore dispersal, including ectomycorrhizal (ECM) fungi symbiotic with forest-forming trees. As such, fungi and their symbionts may be impacted by mycovore extinction. New Zealand (NZ) has a diversity of unusual, colourful, endemic sequestrate (truffle-like) fungi, most of which are ECM. As NZ lacks native land mammals (except bats), and sequestrate fungi are typically drab and mammal-dispersed, NZ’s sequestrate fungi are hypothesized to be adapted for bird dispersal. However, there is little direct evidence for this hypothesis, as 41% of NZ’s native land bird species became extinct since initial human settlement in the thirteenth century. Here, we report ancient DNA and spores from the inside of two coprolites of NZ’s extinct, endemic upland moa (Megalapteryx didinus) that reveal consumption and likely dispersal of ECM fungi, including at least one colourful sequestrate species. Contemporary data from NZ show that birds rarely consume fungi and that the introduced mammals preferentially consume exotic fungi. NZ’s endemic sequestrate fungi could therefore be dispersal limited compared with fungi that co-evolved with mammalian dispersers. NZ’s fungal communities may thus be undergoing a gradual species turnover following avian mycovore extinction and the establishment of mammalian mycovores, potentially affecting forest resilience and facilitating invasion by exotic tree taxa.

Keywords: evolutionary anachronism, moa, New Zealand, extinction, ancient DNA, mycophagy

(a) Upland moa skeleton, (b) HC coprolite X17/11/33,
and (c–h) examples of fungi identified from aDNA (* denotes taxa with congruent spore evidence):
(c) Gallacea scleroderma*, (d) Gallacea sp. ‘Nelson Lakes’*, 
(e) Rossbeevera pachydermis*, (f) Russula macrocystidiata*,
(g) Cortinarius sp. ‘Blyth Track’, (h) Cortinarius violaceovolvatus.

Photo credits: (a) Wikimedia Commons, (b) Alexander P. Boast, (c–h) Noah Siegel.

Alexander P. Boast, Jamie R. Wood, Jerry Cooper, Nic Bolstridge, George L. W. Perry and Janet M. Wilmshurst. 2025. DNA and Spores from Coprolites reveal that Colourful Truffle-like Fungi endemic to New Zealand were consumed by extinct Moa (Dinornithiformes). Biol. Lett. 2120; 240440. DOI: doi.org/10.1098/rsbl.2024.0440  

[Paleontology • 2024] Benggwigwishingasuchus eremicarminis • A New pseudosuchian (Archosauria: Pseudosuchia) from the Favret Formation of Nevada reveals that Archosauriforms occupied Coastal Regions globally during the Middle Triassic

Benggwigwishingasuchus eremicarminis 

Smith, Klein, Sander & Schmitz, 2024 

DOI: 10.1098/rsbl.2024.0136

Abstract

Recent studies suggest that both stem- and crown-group Archosauria encompassed high ecological diversity during their initial Triassic radiation. We describe a new pseudosuchian archosaur, Benggwigwishingasuchus eremicarminis gen. et sp. nov., from the Anisian (Middle Triassic) Fossil Hill Member of the Favret Formation (Nevada, USA), a pelagic setting in the eastern Panthalassan Ocean characterized by the presence of abundant ammonoids and large-bodied ichthyosaurs. Coupled with archosauriforms from the eastern and western Tethys Ocean, Benggwigwishingasuchus reveals that pseudosuchians were also components of Panthalassan ocean coastal settings, establishing that the group occupied these habitats globally during the Middle Triassic. However, Benggwigwishingasuchus, Qianosuchus, and Ticinosuchus (two other pseudosuchians known from marine sediments) are not recovered in a monophyletic group, demonstrating that a nearshore marine lifestyle occurred widely across Archosauriformes during this time. Benggwigwishingasuchus is recovered as part of an expanded Poposauroidea, including several taxa (e.g. Mandasuchus, Mambawakalae) from the Middle Triassic Manda Beds of Tanzania among its basally branching members. This implies a greater undiscovered diversity of poposauroids during the Early Triassic, and supports that the group, and pseudosuchians more broadly, diversified rapidly following the End-Permian mass extinction.

Class Reptilia Linnaeus, 1758

Archosauriformes  

Archosauria  

Pseudosuchia  

Poposauroidea  

Benggwigwishingasuchus eremicarminis gen. et sp. nov.
Holotype skeleton (LACM-DI 158616) (a) (pelvis block mirrored for articulation); and interpretive drawing (b)  

Genus Benggwigwishingasuchus

Benggwigwishingasuchus eremicarminis gen. et sp. nov.

  Holotype: LACM-DI 158616, a partially articulated skeleton, including some cranial elements but most of the axial column, girdles and limbs.

  Diagnosis: Mid-sized pseudosuchian (total length: approximately 1.5 m; femur length: 17.75 cm) diagnosed by the following unique combination of characters (*indicates autapomorphy, †indicates autapomorphy inferred from phylogenetic analysis): semilunate eminence on middle of ventral ramus of prefrontal*; ventral ramus of prefrontal broadly exposed in lateral view, extensive ventrally and excludes lacrimal from orbit; supratemporal fossa well-exposed dorsally on parietal; high cervical vertebrae count (10–11); low dorsal vertebrae count (10–11)*; dorsal vertebrae with well-developed laminae and deep infradiapophyseal fossae; anterior caudal vertebrae with well-developed, spatulate ribs; anterior caudal ribs asymmetrical in dorsal view, with diagonal bevel on posterolateral edge*; weakly sinusoidal fibular shaft; metatarsal IV longer than metatarsal III†; metatarsal IV subequal in length to metatarsal II†; robust lateral plantar tubercle on ventral face of metatarsal V; dorsal osteoderms in one-to-one, mirrored alignment in dorsal aspect†; osteoderms with indentations creating an ‘hourglass’ waisting in dorsal view*; osteoderms with multiple short spikes on lateral and medial edges.

  Etymology: The generic name combines ‘Benggwi Gwishinga’ from the Shoshone term for ‘catching fish’, with ‘suchus’, the Greek term for Sobek, the Egyptian crocodile-headed god. The specific epithet combines the Latin ‘erema’ and ‘carminis’, meaning ‘desert song’, and honours Elaine Kramer and Monica Shaffer, and their love of the palaeontology, museums, and opera of the southwestern USA. The binomen is intended to translate roughly as ‘Fisherman Croc's desert song’.

Middle Triassic palaeogeographic map with localities of Archosauriformes known from marine settings.

  Locality and age: Fossil Hill Member of the Favret Formation, Favret Canyon, Augusta Mountains, Pershing County, Nevada, USA. The type locality, LACM LOC 8057, is near the top of the north slope of Favret Canyon at an altitude of 1911 m. The horizon pertains to the Frechites occidentalis Zone, which is late Anisian (Middle Triassic) in age.

Nathan D. Smith, Nicole Klein, P. Martin Sander and Lars Schmitz. 2024. A New pseudosuchian from the Favret Formation of Nevada reveals that Archosauriforms occupied Coastal Regions globally during the Middle Triassic. Biol. Lett. 2020240136. DOI: doi.org/10.1098/rsbl.2024.0136

[Paleontology • 2024] Peltocephalus maturin • The Latest Freshwater Giants: A New Peltocephalus (Pleurodira: Podocnemididae) Turtle from the Late Pleistocene of the Brazilian Amazon

Peltocephalus maturin 

Ferreira, Nascimento, Cadena, Cozzuol, Farina, Pacheco, Rizzutto & Langer, 2024

DOI: 10.1098/rsbl.2024.0010 

  twitter.com/GSFerreiraBio

artwork by Júlia d'Oliveira

 

Abstract

Overkill of large mammals is recognized as a key driver of Pleistocene megafaunal extinctions in the Americas and Australia. While this phenomenon primarily affected mega-mammals, its impact on large Quaternary reptiles has been debated. Freshwater turtles, due to the scarcity of giant forms in the Quaternary record, have been largely neglected in such discussions. Here we present a new giant podocnemidid turtle, Peltocephalus maturin sp. nov., from the Late Pleistocene Rio Madeira Formation in the Brazilian Amazon, that challenges this assumption. Morphological and phylogenetic analyses of the holotype, a massive partial lower jaw, reveal close affinities to extant Amazonian species and suggest an omnivorous diet. Body size regressions indicate Pe. maturin possibly reached about 180 cm in carapace length and is among the largest freshwater turtles ever found. This finding presents the latest known occurrence of giant freshwater turtles, hinting at coexistence with early human inhabitants in the Amazon.

 Peltocephalus maturin sp. nov.: photographs (a), outlines (b) and 3D renderings (c) of the dentary MERO.PV.H 007,
and 3D renderings of Pe. dumerilianus lower jaw (d) in left lateral (left), dorsal (centre) and ventral (right) views.

 Abbreviations: cor.s, suture to the coronoid; fai, foramen alveolare inferius; lar, labial ridge; lir, lingual ridge; mir, midline ridge; orr, orthogonal ridge; pos.s, suture with the posterior bone; trs, triturating surface; rha, rhamphotheca posterior limit; scm, sulcus cartilagini meckeli; syf, symphyseal fossa; syh, symphyseal hook; syp, symphyseal pits.

 

 Systematic palaeontology

Testudines Batsch, 1788  

Pleurodira Cope, 1864 

Podocnemididae Cope, 1868 

Peltocephalus Dumeril and Bribon, 1835

Peltocephalus maturin sp. nov.

Diagnosis: Peltocephalus maturin is assigned to Pelomedusoides based on its fused dentaries and to Peltocephalus by the symphyseal hook higher than the coronoid process, the lingual platform and a small fossa with two pits on the posterior surface of the symphysis. It differs from Podocnemis spp. in its straight, instead of curved, labial and lingual ridges, U-shaped midline outline of the lingual ridges, well-developed symphyseal hook, transverse posterior (lingual) platform ventral to the triturating surface and the symphyseal fossa; from Erymnochelys madagascariensis by two pits in the symphyseal fossa, instead of one; from both Podocnemis spp. and E. madagascariensis in its dorsoventrally—instead of posteroventrally—sloping posterior limit of the rhamphotheca. Peltocephalus maturin can be distinguished from Pe. dumerilianus based on its much greater size, labial ridge higher than the lingual, symphyseal ridge separating left and right triturating surfaces (all these shared with Stupendemys geographica), and secondary ridge orthogonal to the long axis of the triturating surface, separating anterior and posterior triturating areas (autapomorphy). Peltocephalus maturin can be differentiated from S. geographica by narrow instead of expanded triturating surfaces, upcurved pointed symphyseal hook and sharp but not protruding and anteriorly V-shaped lingual ridges, instead of protruding and U-shaped.

Etymology: Maturin refers to the giant turtle that vomited out the universe in Stephen King's stories, which in turn was inspired by the character Stephen Maturin who, in the book H.M.S. Surprise of Patrick O'Brian's Aubrey-Maturin series, names a giant tortoise.

G. S. Ferreira, E. R. Nascimento, E. A. Cadena, M. A. Cozzuol, B. M. Farina, M. L. A. F. Pacheco, M. A. Rizzutto and M. C. Langer. 2024. The Latest Freshwater Giants: A New Peltocephalus (Pleurodira: Podocnemididae) Turtle from the Late Pleistocene of the Brazilian Amazon. Biol. Lett. 2020240010. DOI: 10.1098/rsbl.2024.0010 

  twitter.com/GSFerreiraBio/status/1767823411605090740

[Paleontology • 2018] Macrocollum itaquii • An Exceptionally Preserved Association of Complete Dinosaur Skeletons Reveals the Oldest Long-necked Sauropodomorphs (Sauropodomorpha: Unaysauridae)

Macrocollum itaquii  

 Müller, Langer & Dias-da-Silva, 2018

DOI: 10.1098/rsbl.2018.0633 

Abstract

The rise of sauropodomorphs is still poorly understood due to the scarcity of well-preserved fossils in early Norian rocks. Here, we present an association of complete and exceptionally well-preserved dinosaur skeletons that helps fill that gap. They represent a new species, which is recovered as a member of a clade solely composed of Gondwanan Triassic taxa. The new species allows the definition of a set of anatomical changes that shaped sauropodomorph evolution along a period from 233 to 225 Ma, as recorded in the well dated Late Triassic beds of Brazil. In that time span, apart from achieving a more herbivorous diet, sauropodomorph dinosaurs increased their size in a ratio of 230% and their typical long neck was also established, becoming proportionally twice longer than those of basal taxa. Indeed, the new dinosaur is the oldest-known sauropodomorph with such an elongated neck, suggesting that the ability to feed on high vegetation was a key trait achieved along the early Norian. Finally, the clustered preservation mode of the skeletons represents the oldest evidence of gregarious behaviour among sauropodomorphs.

    

Systematic palaeontology

Dinosauria Owen, 1842

Saurischia Seeley, 1887

Sauropodomorpha Huene, 1932

Unaysauridae clade nov.

 Type genus: Unaysaurus tolentinoi Leal et al., 2004.

  Definition: Most inclusive clade including Unaysaurus tolentinoi Leal et al., 2004, but not Plateosaurus engelhardti von Meyer, 1837 nor Saltasaurus loricatus Bonaparte & Powel, 1980.

  Diagnosis: Unaysauridae differs from all other sauropodomorphs by a substantial cranial expansion of the medial condyle of the astragalus. In addition, a promaxillary fenestra is also unique for the group of sauropodomorphs, although cranial elements are still unknown for Jaklapallisaurus asymmetrica.

Macrocollum itaquii gen. et sp. nov.

  Etymology: The generic name combines the Greek word μακρο (= long) and the Latin word ‘collum’ (= neck), referring to the elongated neck of the new taxon. The specific epithet honours Mr José Jerundino Machado Itaqui, one of the main actors behind the creation of CAPPA/UFSM.

 

 Locality and horizon: The specimens were collected at the Wachholz site (29°36′46.42″ S; 53°15′54.06″ W), Agudo, Rio Grande do Sul, Brazil; upper portion of the Candelária Sequence, Paraná Basin. Stratigraphically correlated beds from a nearby site were dated as early Norian (ca 225.42 ± 0.37), Late Triassic.

 Diagnosis: Macrocollum itaquii differs from all other known sauropodomorphs based on a unique combination of characters: antorbital fossa perforated by a promaxillary fenestra; medial margin of the supratemporal fossa with a simple smooth curve at the frontal/parietal suture; proximal articular surface of metacarpal I transversely narrow; acetabulum not fully open; ischiadic longitudinal groove not reaching the caudal half of the ischium; absence of trochanteric shelf on the femur; medial condyle of distal femoral articulation subrectangular in distal view; proximal end of metatarsal II with a straight medial margin (see electronic supplementary material, figure S2 for further details).

Rodrigo Temp Müller, Max Cardoso Langer and Sérgio Dias-da-Silva. 2018. An Exceptionally Preserved Association of Complete Dinosaur Skeletons Reveals the Oldest Long-necked Sauropodomorphs.  Biology Letters. 14(11); 20180633.  DOI: 10.1098/rsbl.2018.0633

    

Mom's Phone Call Helps Uncover Oldest Long-Necked Dinosaur on Record shar.es/aa2quM via @LiveScience

Three ancient skeletons, ancestors of giant dinosaurs, unearthed in Brazil  phys.org/news/2018-11-ancient-skeletons-ancestors-giant-dinosaurs.html via @physorg_com

Pesquisadores do Cappa, da UFSM e da USP descobrem mais antigo dinossauro de pescoço longo ufsm.br/2018/11/20/descoberto-no-brasil-o-mais-antigo-dinossauro-de-pescoco-longo/

Three ancient skeletons, ancestors of giant dinosaurs, unearthed in Brazil  phys.org/news/2018-11-ancient-skeletons-ancestors-giant-dinosaurs.html via @physorg_com

[PaleoEntomology • 2023] The Earliest Pollen-loaded Insects from the Lower Permian of Russia

an Permian insect (Tillyardembia antennaeplana) feeding on a pollen cone of ruflorian cordaites

in Khramov, Foraponova et Węgierek, 2023.

DOI: 10.1098/rsbl.2022.0523

reconstruction by Andrey Atuchin. 

 

Abstract

Recent fossil discoveries suggest that the coevolution of insect pollinators and gymnosperms started long before the appearance of flowering plants. One of the keys to understanding the origins of pollination relationships is fossil insects with gymnosperm pollen attached to the body surface. Such fossils are exceedingly rare to find, especially from the Palaeozoic, a time when ambers with insect inclusions were absent. Here, we report compression fossils of Early Permian tillyardembiid insects (Polyneoptera) preserved with pollen on their heads, thoraces, legs and abdomens. This is the earliest finding of pollen-bearing insects, predating the previous oldest record from the Middle Jurassic by ca 120 Ma. Judging by the pollen composition, tillyardembiids visited a narrow range of host plants, including Rufloriaceae (Cordaitales). While it is impossible to say for certain whether tillyardembiids as pollen consumers contributed to pollination, a trophic specialization of this kind could be considered an evolutionary precursor of pollination mutualism.

 Keywords: Palaeozoic, plant-insect interactions, pollination 

An artistic reconstruction of an Early Permian insect (Tillyardembia antennaeplana) feeding on a pollen cone of ruflorian cordaites. 

Artwork: Andrey Atuchin. 

Alexander V. Khramov, Tatiana Foraponova and Piotr Węgierek. 2023. The Earliest Pollen-loaded Insects from the Lower Permian of Russia. Biol. Lett. 1920220523. DOI: 10.1098/rsbl.2022.0523

[Paleontology • 2022] Zuul crurivastator • Palaeopathological Evidence for Intraspecific Combat in Ankylosaurid Dinosaurs

Zuul crurivastator Arbour & Evans, 2017

in Arbour, Zanno & Evans, 2022. 

DOI: 10.1098/rsbl.2022.0404 

 twitter.com/DavidEvans_ROM 

Abstract

Ankylosaurid dinosaurs were heavily armoured herbivores with tails modified into club-like weapons. These tail clubs have widely been considered defensive adaptations wielded against predatory theropod dinosaurs. Here we argue instead that ankylosaurid tail clubs were sexually selected structures used primarily for intraspecific combat. We found pathological osteoderms (armour plates) in the holotype specimen of Zuul crurivastator, which are localized to the flanks in the hip region rather than distributed randomly across the body, consistent with injuries inflicted by lateral tail-swinging and ritualized combat. We failed to find convincing evidence for predation as a key selective pressure in the evolution of the tail club. High variation in tail club size through time, and delayed ontogenetic growth of the tail club further support the sexual selection hypothesis. There is little doubt that the tail club could have been used in defence when needed, but our results suggest that sexual selection drove the evolution of this impressive weapon. This changes the prevailing view of ankylosaurs, suggesting they were behaviorally complex animals that likely engaged in ritualized combat for social dominance as in other ornithischian dinosaurs and mammals.

Keywords: Dinosauria, Ankylosauria, sexual selection, animal weaponry

 

Victoria M. Arbour, Lindsay E. Zanno and David C. Evans. 2022. Palaeopathological Evidence for Intraspecific Combat in Ankylosaurid Dinosaurs. Biol. Lett. 18: 20220404. DOI: 10.1098/rsbl.2022.0404

  twitter.com/DavidEvans_ROM/status/1600289535128059904

 

[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

[Paleontology • 2020] A Paraphyletic ‘Silesauridae' as An Alternative Hypothesis for the Initial Radiation of Ornithischian Dinosaurs

in Müller & Garcia, 2020.

DOI: 10.1098/rsbl.2020.0417

 facebook.com/CAPPAUFSM 

Abstract

Whereas ornithischian dinosaurs are well known from Jurassic and Cretaceous deposits, deciphering the origin and early evolution of the group remains one of the hardest challenges for palaeontologists. So far, there are no unequivocal records of ornithischians from Triassic beds. Here, we present an alternative evolutionary hypothesis that suggests consideration of traditional ‘silesaurids' as a group of low-diversity clades representing a stem group leading to core ornithischians (i.e. unambiguous ornithischians, such as Heterodontosaurus tucki). This is particularly interesting because it fills most of the ghost lineages that emerge from the Triassic. Following the present hypothesis, the lineage that encompasses the Jurassic ornithischians evolved from ‘silesaurids' during the Middle to early Late Triassic, while typical ‘silesaurids' shared the land ecosystems with their relatives until the Late Triassic, when the group completely vanished. Therefore, Ornithischia changes from an obscure to a well-documented clade in the Triassic and is represented by records from Gondwana and Laurasia. Furthermore, according to the present hypothesis, Ornithischia was the first group of dinosaurs to adopt an omnivorous/herbivorous diet. However, this behaviour was achieved as a secondary step instead of an ancestral condition for ornithischians, as the earliest member of the clade is a faunivorous taxon. This pattern was subsequently followed by sauropodomorph dinosaurs. Indeed, the present scenario favours the independent acquisition of an herbivorous diet for ornithischians and sauropodomorphs during the Triassic, whereas the previous hypotheses suggested the independent acquisition for sauropodomorphs, ornithischians, and ‘silesaurids'.

Keywords: evolution, Dinosauria, Mesozoic era, phylogenetics, feeding behaviours, Dinosauromorpha 

Rodrigo Temp Müller and Maurício Silva Garcia. 2020. A Paraphyletic ‘Silesauridae' as An Alternative Hypothesis for the Initial Radiation of Ornithischian Dinosaurs. Biology Letters. 16:20200417. DOI: 10.1098/rsbl.2020.0417

 facebook.com/CAPPAUFSM/photos/3290688631026919/

Sacisaurus helps to fill the hole in the evolution of ornithischians

 phys.org/news/2020-08-sacisaurus-hole-evolution-ornithischians.html

[PaleoIchthyology • 2021] Austelliscus ferox • The Oldest Devonian Circumpolar Ray-finned Fish?

Austelliscus ferox

Figueroa, Weinschütz & Friedman, 2021

 

 DOI: 10.1098/rsbl.2020.0766 

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Abstract

Actinopterygians (ray-finned fishes) are the most diverse group of living fishes, but have a sparse Devonian fossil record restricted to low palaeolatitudes. Here we report a new actinopterygian from the Paraná Basin of Brazil, which occupied a circumpolar position in the Palaeozoic. Available geological evidence supports a Middle Devonian or older age for this taxon, which shares features of the mandibular symphysis with the latest Devonian Tegeolepis. A phylogenetic analysis resolves these two as sister taxa. This new record expands the palaeogeographic distribution of Devonian ray-fins and suggests that gaps in their fossil record might be filled by exploring poorly sampled high-latitude localities within the Malvinokaffric Realm.

Keywords: Osteichthyes, Actinopterygii, Malvinokaffric, palaeopolar, Devonian, Brazil

Subjects

Systematic palaeontology

Osteichthyes Huxley, 1880

Actinopterygii Cope, 1887

Austelliscus ferox gen. et sp. nov.

 Etymology: The generic name references the high palaeolatitude locality (austelli, from the Latin meaning ‘the southern portion'), combined with the Latin suffix for ‘fish' (iscus). Species epithet alludes to the large teeth of the specimen (ferox, from the Latin meaning ‘ferocious').

 Generic diagnosis: Actinopterygian with robust, conical, anteriorly oriented teeth on the dentary, except for the symphysis where teeth point posteriorly; symphysis reflexed posteriorly; jaw ramus constricted posterior to the symphysis. Differs from Tegeolepis in having: large oval replacement sockets in the lingual tooth row (rather than circular); lingual and labial tooth series converge posteriorly (rather than remaining well separated); more substantial post-symphyseal constriction of the dentary; the external surface of dentary ornamented with rounded tubercles anteroventrally and vermiform ornamentation posteriorly (rather than having only sparse tubercles and ridges).

 

 Holotype: MCT890-P, the mould of an incomplete left dentary in part and counterpart.

 

Rodrigo Tinoco Figueroa, Luiz Carlos Weinschütz and Matt Friedman. 2021. The Oldest Devonian Circumpolar Ray-finned Fish? Biology Letters. DOI: 10.1098/rsbl.2020.0766

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