[Paleontology • 2025] Evolutionary and Paleobiogeographic Implications of New carcharodontosaurian, megaraptorid, and unenlagiine Theropod Remains from the upper Lower Cretaceous of Victoria, southeast Australia

 

Cretaceous Australia Landscape
 

in Kotevski, Duncan, Ziegler, Bevitt, Vickers-Rich, Rich, Evans & Poropat, 2025. 

DOI: doi.org/10.1080/02724634.2024.2441903  

artwork by Jonathan Metzger

ABSTRACT

The Early Cretaceous non-avian theropod body fossil record of Victoria, Australia dominantly comprises isolated dental and postcranial remains. Numerous specimens have been collected from both the upper Strzelecki Group (upper Barremian–lower Aptian) and Eumeralla Formation (upper Aptian–lower Albian), yet theropod diversity in each unit remains poorly resolved. In both deposits, specimens pertaining to Megaraptoridae—a clade seemingly endemic to South America and Australia in the Cretaceous—are most frequently encountered. However, evidence of other typically common Gondwanan theropod groups, including Abelisauridae and Carcharodontosauria, has remained unknown. Herein, we describe five new theropod specimens: three tibiae, and two articulated caudal vertebrae with haemal arches, from the upper Strzelecki Group; and a single tibia from the Eumeralla Formation. Two of these tibiae—one each from the upper Strzelecki Group and the Eumeralla Formation—provide the first evidence for Carcharodontosauria in Australia. Two megaraptorid specimens from the upper Strzelecki Group—a tibia, and two caudal vertebrae with haemal arches—demonstrate that this clade had achieved large body size at the time of its first appearance in the fossil record. A tibia from the upper Strzelecki Group is interpreted to represent the Gondwanan dromaeosaur clade Unenlagiinae. Collectively, the new theropod remains described herein strengthen the evidence for mid-Cretaceous faunal interchange between Australia and South America across Antarctica, and highlight the presence of carcharodontosaurians and unenlagiines at high latitudes in the late Early Cretaceous.

Carcharodontosauria indet. right tibia (NMV P221042)
from the Eumeralla Formation of Victoria, Australia.  

Cretaceous Australia Landscape.

artwork by Jonathan Metzger, Museums Victoria

Jake Kotevski, Ruairidh J. Duncan, Tim Ziegler, Joseph J. Bevitt, Patricia Vickers-Rich, Thomas H. Rich, Alistair R. Evans and Stephen F. Poropat. 2025. Evolutionary and Paleobiogeographic Implications of New carcharodontosaurian, megaraptorid, and unenlagiine Theropod Remains from the upper Lower Cretaceous of Victoria, southeast Australia. Journal of Vertebrate Paleontology. e2441903. DOI: doi.org/10.1080/02724634.2024.2441903  

[Paleontology • 2025] Xingxiulong yueorum • A New Species of Xingxiulong (Dinosauria: Sauropodomorpha) from the lower Jurassic Lufeng Formation of Yunnan Province, China

 

Xingxiulong yueorum

Chen, Y.-M. Wang, Zhang, T. Wang & You, 2025

DOI: doi.org/10.1080/08912963.2025.2458130  

ABSTRACT

The Lufeng Formation of Lufeng City, Yunnan Province, China, is one of the most important sedimentary units for understanding the evolution of the Early Jurassic sauropodomorph dinosaurs. Here, a new species of the early-diverging sauropodomorph Xingxiulong from the Lower Jurassic Lufeng Formation is erected on the basis of a postcranial skeleton. Xingxiulong yueorum, sp. nov. is distinguished from Xingxiulong chengi by possessing a pendant-shaped fourth trochanter with distal termination, an astragalus with almost straight dorsal margin of the posterior surface, and pedal digit V with two phalanges. A phylogenetic analysis supports the monophyly of genus Xingxiulong. Both the two species of Xingxiulong have four sacral vertebrae, which are typically associated with the late-diverging sauropodiforms and sauropods, suggesting a complex early evolution within the sauropodomorphs. This discovery adds to the diversity of the sauropodomorphs from the Lufeng Formation and contributes to our understanding of the intricate patterns characterising the early evolution of sauropodomorphs in Asia.

KEYWORDS: Early jurassic, Lufeng, Sauropodomorpha, Xingxiulong, diversity

 

Xingxiulong yueorum, sp. nov.

Xiang-Yuan Chen, Ya-Ming Wang, Qian-Nan Zhang, Tao Wang and Hai-Lu You. 2025. A New Species of Xingxiulong (Dinosauria, Sauropodomorpha) from the lower Jurassic Lufeng Formation of Yunnan Province, China. Historical Biology: An International Journal of Paleobiology

DOI: doi.org/10.1080/08912963.2025.2458130  

[PaleoOrnithology • 2025] Baminornis zhenghensis • Earliest Short-tailed Bird from the Late Jurassic of China

 

 Baminornis zhenghensis

Chen, M. Wang, Dong, G. Zhou, X. Xu, Deng, L. Xu, Zhang, L. Wang, Du, G. Lin, M. Lin & Z. Zhou, 2025  

  

DOI: doi.org/10.1038/s41586-024-08410-z  

Life reconstruction by Zhao Chuang

Abstract

Recent macroevolutionary studies predict a diversification of early birds during the Jurassic period, but the unquestionable Jurassic bird fossil record is limited to Archaeopteryx, which has also been referred to deinonychosaurian dinosaurs by some analyses. Although they have feathered wings, the known Jurassic birds are more similar to non-avialan theropods in having the ancestral long reptilian tail. This is in stark contrast to most Cretaceous and crownward taxa, which have a short tail that terminates in a compound bone called the pygostyle. Here we report on the oldest short-tailed avialan, Baminornis zhenghensis gen. et sp. nov., from the recently discovered Late Jurassic Zhenghe Fauna, which fills a noticeable spatio-temporal gap in the earliest branching avialan fossil record. B. zhenghensis exhibits a unique combination of derived ornithothoracine-like pectoral and pelvic girdles and plesiomorphic non-avialan maniraptoran hand, demonstrating mosaic evolution along stem avialan line. An avialan furcula collected from the same locality is referrable to ornithuromorphs on the basis of our morphometric and phylogenetic analyses. These newly discovered fossils demonstrate the early appearance of highly derived bird features, and together with an anchiornithine fossil from the same locality, they suggest an earlier origin of birds and a radiation of early birds in the Jurassic.

 Baminornis zhenghensis gen. et sp. nov.

 Baminornis zhenghensis from the Zhenghe Fauna.

Life reconstruction by Zhao Chuang

Runsheng Chen, Min Wang, Liping Dong, Guowu Zhou, Xing Xu, Ke Deng, Liming Xu, Chi Zhang, Linchang Wang, Honggang Du, Ganmin Lin, Min Lin  and Zhonghe Zhou. 2025. Earliest Short-tailed Bird from the Late Jurassic of China. Nature. 638, 441–448. DOI: doi.org/10.1038/s41586-024-08410-z 

[Paleontology • 2024] Lishulong wangi • The largest sauropodomorph skull from the Lower Jurassic Lufeng Formation of China

 Lishulong wangi  

 

Q.-N. Zhang​, Jia, Wang, Y.-G. Zhang & You,. 2024 

DOI: doi.org/10.7717/peerj.18629 

 

The Lower Jurassic Lufeng Formation of China has long been recognized for its diverse early-diverging sauropodomorph dinosaurs, with eight genera and ten species, representing more than half the Laurasian records. In this paper, we describe a new genus and species of non-sauropodan sauropodomorph, Lishulong wangi gen. et sp. nov., from Yunnan Province in southwestern China. This new taxon is represented by a partial skeleton including the skull and nine articulated cervical vertebrae, which differs from other Lufeng forms in both cranial and cervical characteristics. It bears several autapomorphies of the nasal process, the maxillary neurovascular foramen, and the cervical neural spine. Phylogenetic analysis reveals that Lishulong is an early-diverging member of the Sauropodiformes, and the sister-taxon of Yunnanosaurus. Elucidating the novel osteology of Lishulong, it possessed the largest sauropodomorph cranial material currently identified from the Lufeng Formation, not only enriches the diversity of the Lufeng dinosaur assemblage, but also enhances our understanding of the character evolution in early-diverging sauropodiforms. Furthermore, information about paleobiogeographic distributions indicates that Early Jurassic sauropodomorphs, especially Chinese taxa, have maintained multiple dispersions and exchanges within Pangaea.

the cranium of Lishulong wangi gen. et sp. nov. 
 Photograph (A) and interpretative line drawing (B), 
in right lateral view and left lateral view.

Systematic Paleontology

Dinosauria Owen, 1842

Saurischia Seeley, 1888

Sauropodomorpha von Huene, 1932 (sensu Sereno, 2007)

Massopoda Yates, 2007

Sauropodiformes Sereno, 2007 (sensu McPhee et al., 2014)

Lishulong wangi gen. et sp. nov.

Holotype: LFGT-ZLJ0011. An associated partial skeleton that includes the cranium and mandible, and nine cervical vertebrae (axis and C3–C10)

Differential diagnosis: A large non-sauropodan sauropodiform dinosaur with the following unique combination of character states (autapomorphies are indicated by an asterisk): width of the anteroventral process of nasal at its base less than that of its anterodorsal process*; size of the neurovascular foramen at the posterior end of the lateral maxillary row not larger than the others*; shape of the supraoccipital is semilunate and wider than high in posterior view; height to length ratio of the dentary greater than 0.2; lingual concavities of the teeth present; lateral expansion at the anterior region of the dorsal surface of the cervical neural spines*.

Type locality and horizon: The specimen was discovered near the Jiudu Village in Konglongshan Town (formerly named Chuanjie Township), Lufeng County, Yunnan Province, China; and the upper-middle part of the Shawan Member of the Lufeng Formation (Fang et al., 2000), Lower Jurassic. Magnetostratigraphic analyses (Cheng et al., 2004; Huang et al., 2005) revealed the age to be Early Jurassic (late Sinemurian–Toarcian).

Etymology: The generic name is from ‘Lishu’ (chestnut tree in Chinese spelling), the name of the locality where the specimen was found, and ‘long’ refers to a dragon (in Chinese spelling); this specific epithet is in honor of Mr. Zheng-Ju Wang, for his great contributions to the early discoveries of vertebrate fossils from Lufeng.

Qian-Nan Zhang​, Lei Jia, Tao Wang, Yu-Guang Zhang and Hai-Lu You​. 2024. The largest sauropodomorph skull from the Lower Jurassic Lufeng Formation of China. PeerJ. 12:e18629 DOI: doi.org/10.7717/peerj.18629 

[Paleontology • 2024] Ardetosaurus viator • A New diplodocine Sauropod from the Morrison Formation, Wyoming, USA

 Ardetosaurus viator

van der Linden, Tschopp, Sookias, Wallaard, Holwerda & Schulp, 2024

 DOI: 10.26879/1380 

  Life reconstruction by Ole Zant. x.com/TheBioBob

ABSTRACT

The Morrison Formation of the western United States is well-known for its high diversity of sauropod dinosaurs. The Howe-Stephens Quarry in northern Wyoming is one of several quarries which has yielded several associated to completely articulated dinosaur specimens, among which a semi-articulated diplodocid specimen, MAB011899, which was excavated in 1993. This diplodocid specimen is represented by posterior cervical, dorsal, sacral, and anterior caudal vertebrae, multiple thoracic ribs, two chevrons, a left coracoid, a left ilium, both pubes and ischia, a left femur, a left tibia, and a left fibula. Through comparative anatomy, we interpret this specimen as a new species of diplodocine sauropod, Ardetosaurus viator gen. et sp. nov. Unambiguous autapomorphies include paired accessory laminae in the spinoprezygapophyseal fossae of posterior cervical and anterior dorsal vertebrae, bifurcating anterior centrodiapophyseal laminae in the anterior dorsal vertebrae, fossae present in the centropostzygapophyseal laminae of the second dorsal vertebra, a low vertebral height/centrum length ratio of the posterior dorsal vertebrae and reduced to absent centroprezygapophyseal laminae in the anterior caudal vertebrae. Local autapomorphic features include single centroprezygapophyseal laminae in the posterior cervical vertebrae and a highly elliptical cross-section of the femoral midshaft. Ardetosaurus viator is the first skeletally mature sauropod specimen described from the Howe-Stephens Quarry. This specimen provides insight into serial variation of vertebral laminae and laminar transitions. Finally, the peculiar morphology of the—often not preserved—first chevron is described in detail, and its possible use in studying sexual dimorphism in sauropods is discussed.

Keywords: sauropod; new genus; new species; Morrison Formation; Diplodocinae; Wyoming

  Skeletal reconstruction of  Ardetosaurus viator MAB011899. Skeletal reconstruction indicating preserved bones (white), excavated bones but subsequently lost (light gray) and not preserved (dark gray). Unknown elements are based on other diplodocines.

Scale bar equals 1 m. Reconstruction by Ole Zant.

SYSTEMATIC PALEONTOLOGY

DINOSAURIA Owen, 1842

SAUROPODA Marsh, 1878

EUSAUROPODA Upchurch, 1995

NEOSAUROPODA Bonaparte, 1986

DIPLODOCOIDEA Marsh, 1884

FLAGELLICAUDATA Harris and Dodson, 2004

DIPLODOCIDAE Marsh, 1884

DIPLODOCINAE Marsh, 1884

ARDETOSAURUS gen. nov.

 

Ardetosaurus viator gen. et sp. nov.

 

Holotype. MAB011899: two cervical vertebrae, 10 dorsal vertebrae, sacrum, five caudal vertebrae, eight dorsal ribs, two chevrons, a left coracoid, a left ilium, both pubes, both ischia, a left femur, a left tibia, and a partial left fibula.

Diagnosis. Ardetosaurus viator is diagnosed by the combination of the following autapomorphies: 1) the presence of distinct, paired accessory laminae in the spinoprezygapophyseal fossae (SPRF) in the posterior cervical and anterior dorsal vertebrae, 2) anteroventrally bifurcating anterior centrodiapophyseal laminae (ACDLs) in the anterior dorsal vertebrae, 3) the presence of centropostzygapophyseal lamina fossae (CPOL-f) in the second dorsal vertebra, 4) a vertebral height/centrum length ratio of <2.5 of the posterior dorsal vertebrae, and 5) reduced or absent centroprezygapophyseal laminae (CPRLs) in the anterior-most caudal vertebrae. Ardetosaurus viator differs from all other diplodocines by having unbifurcated CPRLs in the posterior cervical vertebrae and a highly elliptical femoral cross-section. Ardetosaurus viator differs from Amphicoelias Cope, 1878, in lacking the rounded, lateral projections of the neural spine tip and the thin neural spine base in the dorsal vertebrae; from Barosaurus Marsh, 1890, by having tall cervical neural spines, single midline keels, narrower prezygapophyseal rami in the cervical vertebrae, ten dorsal vertebrae, the presence of ...

Etymology. ‘Ardeto’ is an inflection of Latin ārdēre, meaning ‘to burn.’ It refers to the history of some of the elements, which were either fully destroyed in a fire, or still show burn scars from the fire. ‘saurus, ’ Latinized form of the Greek σαῦρος (saúros), meaning lizard or reptile. ‘viator’ is Latin for traveler, referring to the journey of the specimen from the USA, via Switzerland and Germany, to the Netherlands.

Locality and horizon. Ardetosaurus viator comes from the Howe-Stephens Quarry of northern Wyoming, USA. The quarry is dated, based on magnetostratigraphy and correlation with other sections in the Morrison basin (Maidment and Muxworthy, 2019; Maidment, personal communication, 2022) at 150.44 to 149.21 million years old, placing it in the Kimmeridgian Stage of the Upper Jurassic.

 Quarry map of Ardetosaurus viator MAB011899. Excavation map of the Howe-Stephens Quarry, indicating the major finds from 1992-2000. Individual dinosaurs are color coded, and MAB011899 is coded with dark blue, and named ‘Diplodocus Brösmeli’ herein. The red crosses indicate the missing/lost cervical vertebrae. Note the relatively similar color for ‘Brösmeli’ and ‘David’ (SMA 0086), but their significant separation in the quarry.

 Figure is courtesy of the SMA. Quarry sections equal 1 by 0.5 m.

  Life reconstruction of  Ardetosaurus viator MAB011899.

Illustration by Ole Zant.

The skeleton of Brösmeli is on display in the Oertijdmuseum.

  x.com/TheBioBob

Tom T.P. van der Linden, Emanuel Tschopp, Roland B. Sookias, Jonathan J.W. Wallaard, Femke M. Holwerda, and Anne S. Schulp. 2024. A New diplodocine Sauropod from the Morrison Formation, Wyoming, USA. Palaeontologia Electronica. 27(3): a50. DOI: doi.org/10.26879/1380

palaeo-electronica.org/content/2024/5327-new-diplodocine-sauropod

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[PaleoOrnithology • 2024] Direct Evidence of Frugivory in the Mesozoic Bird Longipteryx contradicts Morphological Proxies for Diet

 Longipteryx, a fossil bird with unusually strong teeth right at the tip of its beak.

in O’Connor, Clark, Herrera, Yang, Wang, Zheng, Hu et Zhou. 2024. 

DOI: doi.org/10.1016/j.cub.2024.08.012

Illustration by Ville Sinkkonen.

Highlights: 

• Unusual enantiornithine Longipteryx with an elongate rostrum predicted to be a faunivore

• Direct evidence indicates Longipteryx was a frugivore, eating gymnosperm “fruits”

• Like crown birds, morphological proxies fail to predict diet in early birds

Summary: 

Diet is one of the most important aspects of an animal’s ecology, as it reflects direct interactions with other organisms and shapes morphology, behavior, and other life history traits. Modern birds (Neornithes) have a highly efficient and phenotypically plastic digestive system, allowing them to utilize diverse trophic resources, and digestive function has been put forth as a factor in the selectivity of the end-Cretaceous mass extinction, in which only neornithine dinosaurs survived. Although diet is directly documented in several early-diverging avian lineages, only a single specimen preserves evidence of diet in Enantiornithes, the dominant group of terrestrial Cretaceous birds. Morphology-based predictions suggest enantiornithines were faunivores, although the absence of evidence contrasts with the high preservation potential and relatively longer gut-retention times of these diets. Longipteryx is an unusual Early Cretaceous enantiornithine with an elongate rostrum; distally restricted dentition; large, recurved, and crenulated teeth; and tooth enamel much thicker than other paravians. Statistical analysis of rostral length, body size, and tooth morphology predicts Longipteryx was primarily insectivorous. Contrasting with these results, two new specimens of Longipteryx preserve gymnosperm seeds within the abdominal cavity interpreted as ingesta. Like Jeholornis, their unmacerated preservation and the absence of gastroliths indicate frugivory. As in Neornithes, complex diets driven by the elevated energetic demands imposed by flight, secondary rostral functions, and phylogenetic influence impede the use of morphological proxies to predict diet in early-diverging avian lineages.

Keywords: trophics, gymnospermous disseminules, consumulites, stomach contents, Cretaceous, Enantiornithes, Aves/Avialae

 

 Longipteryx, a fossil bird with unusually strong teeth right at the tip of its beak.

Illustration by Ville Sinkkonen.

 

Jingmai O’Connor, Alexander Clark, Fabiany Herrera, Xin Yang, Xiaoli Wang, Xiaoting Zheng, Han Hu and Zhonghe Zhou. 2024. Direct Evidence of Frugivory in the Mesozoic Bird Longipteryx contradicts Morphological Proxies for Diet.  Current Biology.  DOI: doi.org/10.1016/j.cub.2024.08.012

[Paleontology • 2024] Qunkasaura pintiquiniestra • A Spanish saltasauroid Titanosaur reveals Europe as a Melting Pot of Endemic and Immigrant Sauropods in the Late Cretaceous

Qunkasaura pintiquiniestra

Mocho, Escaso, Marcos-Fernández, Páramo, Sanz, Vidal & Ortega, 2024. 

DOI: 10.1038/s42003-024-06653-0

Abstract

A new lithostrotian titanosaur, Qunkasaura pintiquiniestra gen. et sp. nov., is described based on a single partial skeleton from the late Campanian-early Maastrichtian fossil-site of Lo Hueco (Cuenca, Spain). This new taxon is supported by an exclusive combination of characters that highlights strong convergences with members of the South American Aeolosaurini. Qunkasaura allows to reorganise the complex phylogenetic relationships of the increasingly diverse finicretaceous sauropods of Europe. Phylogenetic analyses places Qunkasaura within Saltasauridae and possibly Opisthocoelicaudiinae, together with Abditosaurus. A new clade is established, Lohuecosauria, including Saltasaurus, Lohuecotitan, their most recent common ancestor and all its descendants. Two distinct Ibero-Armorican Campanian-Maastrichtian saltasauroid lineages are recognised: (i) Lirainosaurinae that is exclusive from Europe, and (ii) a saltasaurid lineage with possible opisthocoelicaudiine affinities, with a Laurasian distribution. Lirainosaurinae was a relict lineage including possible dwarf forms that evolved in isolation after reaching Europe before the Late Cretaceous through the Apulian route. The occurrence of opisthocoelicaudiines in Europe may be the result of a Late Cretaceous interchange between Europe and Asia. No evidence of insular dwarfism is found in the Ibero-Armorican opisthocoelicaudiines suggesting that they may have been newcomers to the area that arrived before the ‘Maastrichtian Dinosaur Turnover’ in southwestern Europe.

Qunkasaura pintiquiniestra

Pedro Mocho, Fernando Escaso, Fátima Marcos-Fernández, Adrián Páramo, José Luis Sanz, Daniel Vidal and Francisco Ortega. 2024. A Spanish saltasauroid Titanosaur reveals Europe as a Melting Pot of Endemic and Immigrant Sauropods in the Late Cretaceous. Communications Biology. 7: 1016. DOI: doi.org/10.1038/s42003-024-06653-0

  

[Paleontology • 2024] Alpkarakush kyrgyzicus • A new theropod dinosaur (Theropoda: Metriacanthosauridae) from the Callovian Balabansai Formation of Kyrgyzstan

 

Alpkarakush kyrgyzicus 

 Rauhut, Bakirov, Wings, Fernandes & Hübner, 2024

  

DOI: 10.1093/zoolinnean/zlae090

Art by Joschua Knüppe 

Abstract

Recent fieldwork in the late Middle Jurassic Balabansai Formation of Kyrgyzstan has yielded a partial skeleton of a large theropod dinosaur. The material includes a few bones of the skull (postorbital, quadratojugal), dorsal and sacral vertebrae, fragments of the pectoral girdle and forelimbs, and an almost complete pelvic girdle and hindlimbs, and is here made the type of a new theropod taxon, Alpkarakush kyrgyzicus gen. et sp. nov. Alpkarakush can be diagnosed by an extremely developed orbital brow on the postorbital, a pneumatic opening leading into cavities in the neural arch from the centroprezygodiapophyseal fossa in the posterior dorsal vertebrae, an almost enclosed ventral sulcus in manual phalanx II-1, a narrow and deep intercondylar groove on the anterior side of the distal femur, and an epicondylar crest on the distal femur that is offset from the distal end. A second, fragmentary, and smaller specimen from the same site represents the same taxon. Based on long bone histology, the type of Alpkarakush represents a late subadult individual, whereas the smaller specimen is a juvenile, possibly indicating gregarious behaviour. Phylogenetic analysis places Alpkarakush in the Metriacanthosauridae, underlining the diversity and wide distribution of this clade in the Jurassic of Asia.

Central Asia, Middle Jurassic, Tetanurae, Metriacanthosauridae, bone histology

 Outline reconstruction of Alpkarakush kyrgyzicus, with recovered elements indicated. Scale bar is 1 m.

SYSTEMATIC PALAEONTOLOGY

Dinosauria Owen, 1842,

Saurischia Seeley, 1887,

Theropoda Marsh, 1881,

Tetanurae Gauthier, 1986,

Metriacanthosauridae Paul, 1988

Alpkarakush gen. nov.

 

Etymology: Named after Alpkarakush, a mythological large bird [Алпкаракуш] that often comes to the help of heroes in critical moments in the ‘Manas’ epos, one of the central mythological elements in Kyrgyz culture (Seiilbek et al. 2018).

Alpkarakush kyrgyzicus sp. nov.

Etymology: The species epithet refers to the Kyrgyz Republic, the provenance of the type specimen.

Diagnosis: Alpkarakush kyrgyzicus can be diagnosed by the following combination of characters (autapomorphies are indicated by *): extremely developed supraorbital brow on the postorbital, overhanging the orbit; posterior dorsal vertebrae with a channel leading from the centroprezygodiapophyseal fossa posteromedially into pneumatic chambers in the neural arch*; sacral vertebrae with fused neural spines that are approximately as high as the combined height of the vertebral centrum plus neural arch; manual phalanx II-1 with a ventral sulcus proximally that is almost completely enclosed by medial and lateral ventral flanges*; dorsal margin of the ilium slopes steeply posteroventrally*; brevis fossa on ilium reduced to a small medial shelf; shaft of pubis strongly bowed anteriorly; well-developed longitudinal depression on the posterolateral side of the pubic shaft adjacent to the pubic boot (based on paratype); unusually high pubis/tibia ratio (1.22 or higher); articulated ischia with pronounced ischial boots that are convex distally and fused anteriorly, but separated posteriorly; ischium with small obturator flange that is offset from the pubic peduncle; pubic peduncle of ischium very long; iliac articulation in proximal ischium cup-shaped; narrow and deep intercondylar groove on the anterior side of distal femur*; robust and well-developed medial epicondylar crest on distal femur, considerably offset proximally from distal end*; tibia with robust, bulbous fibular flange; astragalus and calcaneum fused.

Type locality and horizon: Locality FTU-1, just west of the town of Tashkumyr, Jalal-Abad Oblast, Kyrgyzstan (Figs 1, 2). The specimens were found in the higher part of the Balabansai Formation, Callovian.

Oliver W. M. Rauhut, Aizek A. Bakirov, Oliver Wings, Alexandra E. Fernandes and Tom R. Hübner. 2024. A new theropod dinosaur from the Callovian Balabansai Formation of Kyrgyzstan. Zoological Journal of the Linnean Society. 201(4); zlae090. DOI: doi.org/10.1093/zoolinnean/zlae090

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[Paleontology • 2024] Campananeyen fragilissimus • They all floated in the Cretaceous: New rebbachisaurid (Sauropoda: Diplodocoidea) with a highly pneumatized skeleton from the Upper Cretaceous (lower Cenomanian) of Patagonia, Argentina

 

 Campananeyen fragilissimus

 Lerzo, Fernández-Baldor, Canale, Whitlock, Otero & Gallina, 2024

DOI: 10.1080/08912963.2024.2383708  

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ABSTRACT

Rebbachisaurids are a group of basal diplodocoid sauropods that diversified primarily in Gondwana between the early Lower Cretaceous and the early Upper Cretaceous. Their phylogenetic relationships are still under debate given the fragmentary and incomplete nature of its remains. Here, we provide a detailed description of the postcranial remains of Campananeyen fragilissimus gen. et sp. nov. from the Candeleros Formation (lower Cenomanian) of Neuquén Province, Argentina. Campananeyen presents notable features that allow it to be recognised as a new species by the presence of an underdeveloped crista prootica, paraoccipital process internally hollow and a fuse dorsal alar arm of the ilium. The phylogenetic analysis recovered this taxon as a basal rebbachisaurid closely related to Zapalasaurus, Sidersaura and the specimen from La Amarga Formation MACN-Pv-N 35. The new rebbachisaurid is recovered as the sister taxon of Sidersaura due the presence of procoelous posterior caudal vertebrae and dorsoventrally flattened posterior caudal centra. C. fragilissimus presents an extreme pneumatization of the sacral region with an autapomorphic dorsal alar arm of the sacral transverse processes. Finally, the phylogenetic analysis supports a South American origin for Rebbachisauridae and an early diversification to Africa and Europe by the Barremian-Aptian as previously suggested.

KEYWORDS: Candeleros formation, Dinosauria, Pneumatization, Gondwana, Campananeyen, Rebbachisauridae

Campananeyen fragilissimus gen. et sp. nov. 

 

Lucas N. Lerzo, Fidel Torcida Fernández-Baldor, Juan I. Canale, John A. Whitlock, Alejandro Otero and Pablo A. Gallina. 2024. They all floated in the Cretaceous: New rebbachisaurid (Sauropoda, Diplodocoidea) with a highly pneumatized skeleton from the Upper Cretaceous (lower Cenomanian) of Patagonia, Argentina. Historical Biology: An International Journal of Paleobiology. DOI: doi.org/10.1080/08912963.2024.2383708  

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[Paleontology • 2024] The Axial Biomechanics of Trigonosaurus pricei (Neosauropoda: Titanosauria) and the importance of the cervical–dorsal region to Sauropod high-browser Feeding Strategy

Trigonosaurus pricei  

in Vidal, Bergqvist, Candeiro, Bandeira, ... et Pereira. 2024. 

DOI: 10.1093/zoolinnean/zlae087 

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Abstract

Trigonosaurus pricei is a small to medium-sized sauropod dinosaur (Sauropoda: Titanosauria) from the Late Cretaceous Bauru Group of Brazil that is known from a significant amount of recovered axial elements [four cervical vertebrae, 10 dorsal vertebrae, sacrum (MCT 1488-R), and 10 caudal vertebrae (MCT 1719-R)]. In this biomechanical work, we approach the hypothesis of the cartilaginous neutral pose and the range of motion of the axial series of Trigonosaurus. The results show that this sauropod could be capable of high elevation of the neck resulting from morphological adaptations of the cervicodorsal region on dorsal (D) vertebrae D2 and D3 (e.g. postzygapophyses of D2 positioned over the vertebral centrum and prezygapophyses of D3 over the anterior vertebral centrum). This implies that D2 articulates (cartilaginous neutral posture) with D3 only at a strong dorsally directed angle, resulting in a shift in the direction of the neck to a more elevated posture. Furthermore, the tail attributed to Trigonosaurus as a paratype could be oriented in the horizontal ‘direction’ and presented a sigmoidal ‘shape’. This work contributes generally to the understanding of variation in the body plan of sauropods and, more specifically, to the feeding strategy of small and medium-sized titanosaurs from semi-arid regions of Gondwana.

vertebrate palaeontology, Suropodomorpha, biomechanics, palaeoecology

Trigonosaurus pricei 

 Luciano S Vidal, Lílian P Bergqvist, Carlos R A Candeiro, Kamila L N Bandeira, Sandra Tavares, Stephen L Brusatte and Paulo V L G C Pereira. 2024. The Axial Biomechanics of Trigonosaurus pricei (Neosauropoda: Titanosauria) and the importance of the cervical–dorsal region to Sauropod high-browser Feeding Strategy. Zoological Journal of the Linnean Society. 201(3); zlae087. DOI: doi.org/10.1093/zoolinnean/zlae087

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