New dinosaur taxa General non-avian dinosaur research • Schwarz
et al. (2023) observe the contents of unopened containers from
Tendaguru Formation (
Tanzania) expeditions via CT scans, and indicate the presence of fossils belonging to dinosaurs including
Dysalotosaurus,
Kentrosaurus, and
Giraffatitan. • A study on causes of recovery of different interrelationships of the three major dinosaur clades (Theropoda, Sauropodomorpha, and Ornithischia) in phylogenetic studies is published by Černý & Simonoff (2023), who find the three possible ways of resolving the relationships among these lineages (Saurischia-Ornithischia, Ornithischiformes-Theropoda and Ornithoscelida-Sauropodomorpha dichotomies) to be statistically indistinguishable and supported by nearly equal numbers of characters in the datasets from the studies of Baron, Norman & Barrett (2017) and Langer
et al. (2017). • A review of the history of morphometric studies in non-avian dinosaurs is published by Hedrick (2023). • Cullen
et al. (2023) reevaluate evidence for anomalously positive stable carbon isotope compositions of dinosaur bioapatite, report that the studied anomaly is present in the carbon isotope compositions of bioapatite in
tooth enamel of not only dinosaurs but also mammals and crocodilians and in scale
ganoine of
gars from the "Rainy Day Site" in the
Campanian Oldman Formation (
Alberta,
Canada) but is absent in extant vertebrates from the near-analogue modern ecosystem in the
Atchafalaya Basin (
Louisiana, United States), and interpret their findings as indicating that the studied anomaly is not the result of a unique dietary physiology of dinosaurs. • A study on the element ratios in the enamel of dinosaurs from the Oldman Formation is published by Cullen & Cousens (2023), who interpret their findings as indicative of differences in habitat use, dietary plant sources and feeding height between hadrosaurs and other ornithischians, as well as indicating that troodontid theropods were mixed-feeding to plant-dominant omnivores. • Dinosaur eggshell fragments with preserved
eggshell membranes are reported from the
Late Jurassic Brushy Basin Member of the
Morrison Formation (
Utah,
United States) by Lazer
et al. (2023). • Oussou
et al. (2023) describe new tracksites with ornithopod, sauropod and theropod (including possible bird-like non-avian theropod) tracks from the Jurassic
Isli Formation (
Morocco). • Navarro-Lorbés
et al. (2023) describe tracks produced by an undetermined bipedal non-avian dinosaur from the Lower Cretaceous Cameros Basin (
Spain), interpreted as likely produced during swimming, and provide information on the swimming behaviour of the trackmaker. • Méndez Torrez
et al. (2023) report the discovery of the first assemblage of dinosaur tracks (dominated by sauropod tracks, including tracks of possible non-
neosauropod eusauropods, and possibly preserving evidence of herd behaviour) from the Jurassic to earliest Cretaceous Castellón Formation (
Bolivia). • Naimi
et al. (2023) describe tracks of small theropods and ornithopods from the
Albian-
Cenomanian strata from the Ouled Nail Mounts, representing some of the stratigraphically youngest records of non-avian dinosaurs in
Algeria reported to date. • Esperante
et al. (2023) report the discovery of a short-lived new site with hundreds of tracks of dinosaurs (subsequently removed because of the construction of a new road) from the
El Molino Formation (Bolivia), including swim traces of theropod dinosaurs. • Description of four dinosaur teeth assignable to three different groups (
Tyrannosauroidea,
Titanosauriformes, and
Hadrosauroidea) from the Cretaceous
Sunjiawan Formation (
China) is published by Yin
et al. (2023), representing the first record of a theropod from the formation, as well as representing potentially two new taxa, as the hadrosauroid teeth are distinct from
Shuangmiaosaurus. • A review of the
Early Cretaceous dinosaur fauna from
Thailand is published by Samathi
et al. (2023). • Li
et al. (2023) report the discovery of sauropod and ornithopod tracks from the
Zonggei Formation, providing evidence for the presence of abundant dinosaurs in the Late Cretaceous of the Tibet region (China). • Flannery-Sutherland
et al. (2023) describe the first dinosaur tracks from the Upper Cretaceous
Nichkesaisk Formation (
Kyrgyzstan), probably produced by both large-bodied and smaller-bodied theropods or ornithopods. • A study on the duration of Late Cretaceous megaherbivore dinosaur assemblage zones in the 100 m thick stratigraphic section exposed at Dinosaur Provincial Park (Alberta, Canada) is published by Eberth
et al. (2023), who interpret their findings as indicating that the dinosaur assemblage zones in the studied section had duration time of ~600–700.000 years, and were significantly shorter than those in the overlying
Horseshoe Canyon Formation. • Review of the Cretaceous non-avian dinosaur egg record from the Gobi Desert of
Mongolia, including descriptions of eggs representing six
ootaxa (
Coralloidoolithus oosp.,
Dendroolithus oosp.,
Macroelongatoolithus oosp.,
Paraspheroolithus irenensis,
cf. Protoceratopsidovum minimum, and cf.
Spheroolithus maiasauroides) from the Upper Cretaceous localities Altan Uul I, Altan Uul IV, Bayanshiree, Shine Us Khudag and Shiluut Uul, is published by Tanaka
et al. (2023). • A study on the stable oxygen and carbon isotope compositions of dinosaur eggshell calcites and tooth apatites from the Upper Cretaceous
Kakanaut Formation (
Chukotka Autonomous Okrug,
Russia) is published by Amiot
et al. (2023), who interpret their findings as indicating that near-polar Kakanaut dinosaurs likely laid eggs in early spring, giving time for the hatchlings to grow before winter. • A review of Cretaceous dinosaurs from India published by Khosla and Lucas (2023).
Saurischian research • An isolated ilium of a probable non-
herrerasaurid herrerasaurian, potentially representing the first record of such a saurischian in unambiguous
Carnian beds, is described from the Pivetta site (Candelária Sequence;
Brazil) by Garcia
et al. (2023). • Silva
et al. (2023) described new herrerasaurid material from the Predebon site (Candelária Sequence of the Santa Maria Supersequence, Brazil), and interpret its anatomy as possibly indicative of the presence of a herrerasaurid
morphotype distinct from
Gnathovorax cabreirai and
Staurikosaurus pricei. • A track site of dinosaur footprints is described from the
Middle Jurassic Xietan Formation (
Hubei,
China) by Xing
et al. (2023), who interpret the tracks as belonging to small sauropods (similar to
Brontopodus) and probable theropods. • Lei
et al. (2023) report theropod bite traces on 68 sauropod bones from the Upper Jurassic
Morrison Formation (
United States), as well as evidence of tooth wear in large-bodied theropods from the Morrison Formation interpreted as indicating that the studied theropods were biting into bone, and consider it most likely that the wear seen on large theropod teeth was mostly caused by contact with the destroyed bones of the more frequently consumed juvenile sauropods, while the studied bite traces were most likely caused by scavenging on carcasses of large-bodied sauropods.
Theropod research • A study on the developmental strategies underlying the evolution of body size of non-avialan theropods is published by D'Emic
et al. (2023), who report that changes in the rate and duration of growth contributed nearly equally to the body size changes. • A study on the relationship between the body size of theropods, the area of muscles important for their balance and locomotion, and their capacity for agility is published by Henderson (2023), who argues that theropod body plan had an upper size limit based on a minimum acceleration threshold. • Cullen
et al. (2023) use multiple lines of evidence, including
histology of teeth and morphological comparisons, to evaluate proposed theropod facial reconstructions, and argue that non-avian theropods most likely had lips that covered their teeth. • Review of hand modifications and hand functions in late non-avian theropods is published by
Barsbold (2023). • Kirmse
et al. (2023) describe a coelophysoid femur from the Tytherington fissures near
Bristol, UK, which cannot be definitively compared and referred to
Pendraig. • Peng
et al. (2023) describe abundant tracks from the Upper Triassic Tianquan track site (
Xujiahe Formation; Ya'an, western Sichuan Basin,
China), interpreted as produced by small theropods and representing one of the earliest record of dinosaurs from the eastern
Tethys realm. • New specimen of
Sinosaurus triassicus, including a complete skull and 11 cervical vertebrae, is described by Zhang, Wang & You (2023). • Purported "
coelophysoid-
grade" tibia from the
Sinemurian of the Isle of Skye (Scotland, United Kingdom) is reinterpreted as fossil material of
cf. Sarcosaurus woodi by
Ezcurra et al. (2023). • Sharma, Hendrickx & Singh (2023) describe dental material of a non-coelurosaur
averostran theropod from the
Bathonian Fort Member of the
Jaisalmer Formation (
India), providing evidence of the presence of at least one taxon of a medium to large-bodied theropod on the
Tethyan coast of India during the Middle Jurassic. • Tracks assigned to the ichnotaxon
cf. Eubrontes, providing evidence of the presence of small theropods within the Hami pterosaur fauna, are described from the Lower Cretaceous
Tugulu Group (Xinjiang, China) by Li
et al. (2023). • Footprints of small theropods with a cursorial gait are described from the Lower Cretaceous
Botucatu Formation (
Brazil) by Leonardi
et al. (2023), who name a new ichnotaxon
Farlowichnus rapidus. • Theropod scrapes from the Cretaceous of
Colorado, originally interpreted as evidence of display arenas or leks of theropods, are argued to be more likely results of failed attempts by theropods to dig near-circular bowls that were to be used as nests by Moklestad &
Lucas (2023). • Review of the fossil record of Abelisauroidea in continental Africa is published by Souza-Júnior
et al. (2023). • Averianov & Lopatin (2023) describe an elongated and highly pneumatized cervical vertebra of a long-necked theropod from the Lower Cretaceous (Aptian)
Ilek Formation (
Kemerovo Oblast,
Russia); subsequently Averianov
et al. (2024) interpret this vertebra as likely belonging to the
holotype specimen of the
noasaurid Kiyacursor longipes. • Barbosa
et al. (2023) study the functional morphology of dental and pedal elements of the skeleton of
Vespersaurus paranaensis, and interpret it as indicating that this theropod had a generalist diet, feeding on small or immobile prey. • Amudeo-Plaza
et al. (2023) interpret a theropod tooth from the Cretaceous (Albian-Turonian) Quebrada La Totora Beds as the first record of an
abelisaurid from
Chile. • Paulina-Carabajal
et al. (2023) report the discovery of a natural cranial
endocast of an abelisaurid from the
Santonian Bajo de la Carpa Formation (
Argentina). • Longrich
et al. (2023) describe new abelisaurid material from the
Ouled Abdoun Basin, interpreted as indicative of coexistence of as many as three abelisaurid taxa in
Morocco during the late
Maastrichtian. • Description of the anatomy of the axial skeleton of
Aucasaurus garridoi is published by Baiano
et al. (2023). • A study on the evolution of the morphological characters of the pelvic girdle, femur, tibia and fibula in early theropods, especially in
megalosauroids, is published by Lacerda, Bittencourt & Hutchinson (2023). • Lacerda, Bittencourt & Hutchinson (2023) present reconstructions of the hindlimb musculature of
Condorraptor currumili,
Marshosaurus bicentesimus and
Piatnitzkysaurus floresi. • Revision of the
spinosaurid taxonomy is published by Terras
et al. (2023). • Pedal ungual
phalanx of a possible spinosaurid is described from the Jurassic (
Bathonian)
Jaisalmer Formation (
India) by Sharma,
Novas & Singh (2023). • A collection of seven isolated spinosaurid teeth as well as a single preungual pedal phalanx of an indeterminate theropod are reported from the Berriasian–Valanginian
Feliz Deserto Formation (Brazil) by Lacerda
et al. (2023). • Barker
et al. (2023) reconstruct the endocasts of the
baryonychine spinosaurids
Baryonyx walkeri and
Ceratosuchops inferodios, finding their morphology to be similar to non-maniraptoriform theropods despite their highly modified skulls. • The first baryonychine teeth from South America reported to date are described from the Lower Cretaceous Feliz Deserto Formation (Brazil) by Lacerda
et al. (2023). • Redescription of the anatomy of the skull of
Irritator challengeri and a study on the affinities of this spinosaurid is published by Schade
et al. (2023). • Description of a pathological tooth of
Spinosaurus from the Late Cretaceous
Ifezouane Formation (
Morocco) is published by Smith and Martill (2023), representing the first record of external dental pathology in a spinosaurine spinosaurid. • Reconstruction of the musculature of the pectoral girdle and forelimbs in
megaraptoran theropods is presented by Aranciaga Rolando
et al. (2023). • A pathological third
metatarsal of
Phuwiangvenator, indicating that the bone experienced a
greenstick fracture and healed before the animal's death, is described from the
Lower Cretaceous Sao Khua Formation (
Khon Kaen,
Thailand) by Samathi
et al. (2023). • A probable
megaraptorid frontal and fused parietal fragment, representing the oldest megaraptorid skull element reported to date, is described from the
Aptian upper Strzelecki Group (the "Wonthaggi Formation";
Australia) by Kotevski
et al. (2023). • A study estimating the number of
telencephalic neurons in theropod dinosaurs is published by
Herculano-Houzel (2023), who argues that
Allosaurus and
Tyrannosaurus are endotherms with baboon- and monkey-like numbers of neurons; however, this study has been criticized. • The study suggesting that
carnosaurs like
Allosaurus were primarily scavengers that fed on sauropod carcasses, originally published by Pahl and Ruedas (2021) is criticized by Kane
et al. (2023) but later defended by Pahl and Ruehdas (2023). • Description of the endocranial anatomy of
Allosaurus fragilis and
A. jimmadseni is published by Lessner
et al. (2023). • Yu
et al. (2023) describe a probable
metriacanthosaurid tooth from the Middle Jurassic Dongdaqiao Formation (China), interpret its morphological similarities to
velociraptorine teeth as most likely resulting from
convergent evolution, and argue that other Jurassic dromaeosaurid-like teeth from the Jurassic deposits of Asia and Europe might be teeth of non-dromaeosaurid theropods. • Carrano (2023) describes an incomplete theropod skeleton from the Lower Cretaceous
Arundel Clay (
Maryland,
United States), representing the first definitive record of
Acrocanthosaurus from the eastern part of North America reported to date. • Zhang
et al. (2023) report the discovery of fossil downy feathers of coelurosaurs from the Lower Cretaceous Zhonggou Formation (China), with macromorphology (including rachis, barbs and barbules) essentially the same as in modern bird feathers, but with the microscopic morphology noticeably different from that of living bird feathers. • Johnson-Ransom
et al. (2023) estimate bite force and cranial stresses in tyrannosauroid theropods, and interpret their findings as indicative of greater cranial stress and greater bite force in tyrannosaurids than in early-diverging tyrannosauroids. •
Carr (2023) redescribes the hindlimb of the
lectotype of
Alectrosaurus olseni, describes a partial tyrannosauroid skull from the
Iren Dabasu Formation (China) with similarities to skulls of
Raptorex kriegsteini and juvenile
Tyrannosaurus rex, and questions the assignment of fossil material from Mongolia and Uzbekistan to the genus
Alectrosaurus. • Yun (2023) describes a tyrannosaurid pedal ungual from the
Williams Fork Formation of
Colorado (
USA). • Therrien
et al. (2023) describe a juvenile specimen of
Gorgosaurus libratus from the
Dinosaur Park Formation (Alberta, Canada), preserved with remains of two specimens of
Citipes elegans within their first year of life in its abdominal cavity, and interpret this finding as indicating that
G. libratus underwent a dietary shift over the course of its life. • New fossil material of
Albertosaurus sarcophagus, including the left pubis with tooth traces interpreted as evidence of cannibalism, is described from the Danek Bonebed (
Horseshoe Canyon Formation; Alberta, Canada) by Coppock &
Currie (2023). • A study on the affinities of
tyrannosaurines, reanalyzing the dataset of Warshaw & Fowler (2022), is published by Scherer & Voiculescu-Holvad (2023), who name a new clade
Teratophoneini, and find no support for a single
anagenetic lineage within derived tyrannosaurines; their findings are subsequently contested by Warshaw, Barrera Guevara & Fowler (2024), whose phylogenetic analysis indicates that recognized
Daspletosaurus species represent a single anagenetic lineage ancestral to
Tyrannosaurus-line tyrannosaurines. •
Fiorillo et al. (2023) report the discovery of a theropod track from the
Chignik Formation (
Alaska,
United States) produced by a tyrannosaur larger than
Nanuqsaurus hoglundi, and interpret this finding as suggestive of different selective pressures on tyrannosaurids between the northern and southern extremes of Alaska. • Hodnett
et al. (2023) report on a tyrannosaur tooth (assigned to
cf. Tyrannosaurus sp.) from the
Harebell Formation (
Wyoming, United States), marking the first confirmed record of a dinosaur fossil discovered within the
Yellowstone National Park. • Evidence of preservation of elements associated with bone remodeling and redeposition (sulfur, calcium, zinc) in a specimen of
Tyrannosaurus rex, interpreted as indicative of preservation of original endogenous chemistry in the studied specimen, is presented by Anné
et al. (2023). • A study on the formation and function of the enlarged
unguals of alvarezsauroid and therizinosaur theropods is published by Qin
et al. (2023), who interpret their findings as indicative of the evolution of digging adaptions in late-diverging alvarezsauroids, find the unguals of early-branching therizinosaurs to perform well in piercing and pulling, and interpret the enlarged unguals of
Therizinosaurus as not adapted to functions that required considerable stress-bearing. • A study on the hindlimb variation between the best-preserved specimens of putative ornithomimosaurs from the
Angeac-Charente bonebed (
France) is published by Pintore
et al. (2023), who interpret their findings as indicative of the presence of sexual dimorphism in the studied theropods. • Two ornithomimid
pedal phalanges are described from the Late Cretaceous
Fox Hills Formation (
South Dakota,
United States) by Chamberlain, Knoll, and Sertich (2023), representing the first dinosaur skeletal material from the formation. • Averianov
et al. (2023) describe an ornithomimid tibia from the Maastrichtian
Udurchukan Formation, (
Amur Oblast,
Russia), representing the first finding of an ornithomimid in the Upper Cretaceous strata from the Russian Far East reported to date. • A study on the bone histology of the holotype specimen of
Parvicursor remotus is published by Averianov
et al. (2023), who interpret this specimen as a young individual, not more than one year old, and reevaluate the course of alvarezsaurid miniaturization inferred by Qin
et al. (2021), finding no compelling morphological data indicating that
parvicursorine alvarezsaurids fed on colonies of social insects and that their miniaturization was related to myrmecophagy. • A study on the range of motion at the shoulder in
Mononykus olecranus is published by Senter (2023). • Wills, Underwood & Barrett (2023) identify therizinosauroid and troodontid teeth, as well as three morphotypes of dromaeosaurid teeth, in a sample of isolated theropod teeth from the Middle Jurassic (
Bathonian) microvertebrate sites in the
United Kingdom. • Reconstruction of the hindlimb musculature of
Falcarius utahensis is presented by Smith (2023). • Smith & Gillette (2023) reconstruct soft tissues of the hindlimbs and likely posture of
Nothronychus graffami. • Skeletal indicators of a
propatagium are investigated by Uno & Hirasawa (2023), supporting the presence of this structure in non-avian
pennaraptorans such as
Caudipteryx and
Microraptor. • A review of the evidence for partially buried eggs and their significance for the evolution of contact
incubation in Mesozoic
pennaraptorans is published by Hogan & Varrcchio (2023). • Averianov & Lopatin (2023) describe fossil material (metatarsals) of a caenagnathid with similaries to
Elmisaurus rarus and a dromaeosaurid with similarities to
Velociraptor mongoliensis from the Upper Cretaceous
Bostobe Formation (
Kazakhstan). • Voris,
Zelenitsky & Therrien (2023) describe new caenagnathid fossil material from the upper Maastrichtian portion of the
Scollard Formation (
Alberta,
Canada), including fossils indicative of the presence of a large-bodied taxon similar to
Anzu wyliei or
Caenagnathus collinsi. • The most complete caenagnathid specimens from the southern part of North America reported to date are described from the Campanian
Aguja Formation (
Texas,
United States) by Wick, Lehman & Fortner (2023), who present a histology-based growth model for one of the studied specimens (the first for a caenagnathid), indicating that it needed least five years to approach fully adult size. • The feasibility of contact
incubation by
oviraptorids based on their nest architecture is experimentally tested by Hogan (2023). • A review of bone microstructure and
histology in
dromaeosaurids and
troodontids is published by Martin, Currie & Kundrát (2023). • Yang
et al. (2023) report the first discovery of fossil materials of a large-bodied dromaeosaurid (probably a eudromaeosaur) from the Upper Cretaceous
Quantou Formation (Jilin, China). • Croudace
et al. (2023) reconstruct the feather colouration of an approximately one-year-old individual of
Wulong bohaiensis, reporting evidence indicative of the presence of iridescent plumage of the forelimb and hindlimb remiges and grey plumage on other portions of the body. • A partial left tibia and
articulated proximal tarsals, likely belonging to an indeterminate
velociraptorine, are described from the
Upper Cretaceous Lo Hueco fossil site (
Cuenca,
Spain) by Malafaia
et al. (2023), who also review the European theropods of the Late Cretaceous. • Averianov & Lopatin (2023) describe new fossil material of
Kansaignathus sogdianus from the Santonian
Ialovachsk Formation (
Tajikistan), and confirm the phylogenetic placement of
K. sogdianus as the
basalmost Asiatic velociraptorine. • Czepiński (2023) describes a specimen of
Shri devi with a partial skull from the Upper Cretaceous
Barun Goyot Formation (
Mongolia), and reports that the anatomy of the skull confirms close affinities of
Shri with
Velociraptor mongoliensis, but also that the skull has anatomical features suggesting
convergence to the North American
eudromaeosaurians. • A study on the nasal structures of
Velociraptor mongoliensis, indicating that this theropod was unlikely to have a fully developed nasal thermoregulation apparatus for its brain as seen in modern birds, is published by Tada
et al. (2023). • A study on the bone histology of the
holotype of
Liaoningvenator curriei is published by Martin, Caizhi & Kundrát (2023), who interpret their findings as indicative of a growth pattern transitive between those of
basalmost and more derived
troodontids. • Evidence from eggshells of
Troodon, interpreted as indicative of endothermic physiology but also of reptile-like eggshell mineralization process, is presented by Tagliavento
et al. (2023).
Sauropodomorph research • Lockley
et al. (2023) evaluate a number of trackways assigned to basal saurischians, including those belonging to the ichnogenera
Otozoum,
Pseudotetrasauropus,
Evazoum, and
Kalosauropus, and examine their implications on the gait of "
prosauropods". • A new specimen of
Buriolestes schultzi, interpreted as stouter than other specimens of
B. schultzi and providing evidence of previously unknown variation in robustness within this species, is described from the Late Triassic of southern
Brazil by Moro
et al. (2023). • A study on sauropodomorph tracks from the Upper Triassic lower Elliot Formation (
Lesotho) is published by Sciscio
et al. (2023), who interpret the studied tracks as confirming that sauropodomorphs already evolved large body size by the
Norian, but also indicating that the makers of the studied tracks used both bipedal and quadrupedal locomotion styles during a 10-million-years interval in the Norian. • Chapelle, Botha & Choiniere (2023) study the histology of a small sauropodomorph humerus from the upper Elliot Formation (
South Africa), and interpret this specimen as a bone of a skeletally mature individual of a new taxon with a body mass of approximately 75.35 kg, representing the smallest known Jurassic sauropodomorph reported to date. • New information on the anatomy of
Jaklapallisaurus asymmetricus is presented by
Ezcurra et al. (2023), who interpret
J. asymmetricus as a member of
Unaysauridae. • Müller
et al. (2023) describe the remains of a juvenile specimen of
Unaysaurus, found associated with the holotype, from the Late Triassic
Caturrita Formation (
Brazil). • Taxonomic revision of
basal sauropodomorph specimens stored in the Palaeontological Collection of Tübingen, historically referred to the genus
Plateosaurus, is published by Regalado Fernandez
et al. (2023). • Aureliano
et al. (2023) provide evidence of the presence of an invasive air sac system in
Macrocollum itaquii. • Bem & Müller (2023) report the first discovery of the fossil material of
Macrocollum itaquii outside its type locality. • Moopen
et al. (2023) describe material of a probable
lessemsaurid from the Triassic lower Elliot Formation and estimating it to be one of the largest sauropodomorphs from the Norian of
South Africa, as well as the first plant-vertebrate fossil associations in the formation. • A study on the evolution of sauropod body mass is published by D'Emic (2023), who finds that sauropods independently surpassed the maximum body mass of terrestrial mammals at least three dozen times in their evolutionary history. • Description of the anatomy of a partial juvenile sauropod vertebral series from the Middle Jurassic
Nam Phong Formation (
Thailand), interpreted as indicative of non-
eusauropod affinities of the studied specimen, is published by Hanta
et al. (2023). • Description of new eusauropod fossil material from the Middle Jurassic
Dongdaqiao Formation (
China) is published by Wei
et al. (2023), who interpret these findings as showing that gigantic sauropods were more widespread than previously known during the Middle Jurassic. • A juvenile sauropod specimen, most closely resembling early-diverging eusauropods from the Middle Jurassic but sharing some derived features with the Late Jurassic mamenchisaurids and neosauropods, is described from the Middle Jurassic
Dongdaqiao Formation (East Tibet, China) by An
et al. (2023). • The holotype of
Mamenchisaurus sinocanadorum is redescribed by Moore
et al. (2023), who also interpret
Bellusaurus and
Daanosaurus as juvenile
mamenchisaurids. • A tooth of a possible member of
Turiasauria, which might represent the oldest record of the group reported to date, is described from the Lower Jurassic (
Pliensbachian) Halse Formation (
Denmark) by Milàn &
Mateus (2023). • A study on the anatomy of the skull of
Bajadasaurus pronuspinax is published by Garderes
et al. (2023). • A study on bifurcated cervical ribs in
apatosaurines is published by
Wedel &
Taylor (2023), who interpret the studied structures as divergent muscle attachments, likely enabling improved muscular control in the middle of the neck. • A rebbachisaurid vertebra from the
La Amarga Formation (
Argentina) is redescribed by Lerzo (2023), who finds it to be a derived member of
Rebbachisaurinae. • A study on the microanatomy of the long bones of
Nigersaurus taqueti is published by Lefebvre, Allain & Houssaye (2023), who interpret their findings as indicating that microanatomical structure in sauropod limb bones was not subject to drastic selective pressures imposed by heavy weight-bearing. • New rebbachisaurid specimen, providing new information on the anatomy of the hindlimbs of rebbachisaurids, is described from the Cenomanian
Huincul Formation (Argentina) by Bellardini
et al. (2023). • Torcida Fernández-Baldor
et al. (2023) describe a dentary and several teeth of a
basal macronarian close to
Camarasaurus from the Valdepalazuelos site (
Rupelo Formation;
Spain) living during the
Tithonian–
Berriasian transition, providing evidence of the presence of two macronarian taxa at the Valdepalazuelos site. • Cervical vertebra representing the first record of a
titanosauriform sauropod from the Lower Cretaceous Kanmon Group (
Japan) is described by Tatehata, Mukunoki & Tanoue (2023). • Sauropod fossil material, including a vertebra of a possible member of the genus
Ornithopsis, is described from the Lower Cretaceous sediments from the Balve II locality (
Germany) by Hornung, Sachs & Schwermann (2023), representing the first finding of sauropod fossils from the upland environment in Europe reported to date. • New information on the
pneumatization of the ribs of the
holotype specimen of
Brachiosaurus altithorax is presented by Taylor & Wedel (2023). • Lim
et al. (2023) report the discovery of a fibula of a member of the family
Euhelopodidae from the strata of the Lower Cretaceous
Grès supérieurs Formation at Koh Paur island, representing the first finding of a non-avian dinosaur from
Cambodia reported to date. • Cruzado-Caballero
et al. (2023) describe two new cases of caudal pathology in titanosaurs from the Late Cretaceous of Argentina and evaluate these cases for interpreting the commonness of pathology occurring in the fossil record. • The pneumaticity of a titanosaur specimen from the
Black Peaks Formation (
Texas,
United States) is investigated by Fronimos (2023). • Averianov
et al. (2023) describe a series of caudal vertebrae representing the first sauropod material from the Shestakovo 3 locality from the Lower Cretaceous
Ilek Formation (
Kemerovo Oblast,
Russia), and interpret it as new fossil material of
Sibirotitan astrosacralis. • New specimen of
Diamantinasaurus matildae, including the skull preserving cranial elements not previously known for this taxon and showing similarities with the skull of
Sarmientosaurus musacchioi, is described from the Upper Cretaceous
Winton Formation (
Australia) by Poropat
et al. (2023). • Titanosaur teeth representing three distinct
morphotypes, including the largest titanosaur tooth ever found, are described from the Upper Cretaceous
Serra da Galga Formation (
Brazil) by Silva Junior
et al. (2023). • Dhiman
et al. (2023) report the discovery of 92 titanosaur egg clutches from the Upper Cretaceous
Lameta Formation (
Madhya Pradesh,
India), including three types of clutches and assigned to six
oospecies, interpret their findings as suggestive of higher diversity of titanosaur taxa from the Lameta Formation than indicated by body fossils, and evaluate the implications of the studied egg clutches for the knowledge of the reproductive biology of titanosaurs. • A study on the bone histology of
Uberabatitan ribeiroi, providing evidence of rapid, uninterrupted growth that ceased with the appearance of periodic interruptions in the advanced stages of development, is published by Windholz
et al. (2023). • A study on the long bone histology of
Muyelensaurus pecheni and
Rinconsaurus caudamirus is published by González
et al. (2023), who find no evidence of a correlation between the ontogenetic stage and the body size in both taxa, unlike in other neosauropods. • A new sauropod specimen (a
saltasaurid humerus) is described from the
Campanian deposits from the
Quseir Formation (
Egypt) by Wahba
et al. (2023). • A sauropod tooth assigned to the family Opisthocoelicaudiidae, representing the first record of a sauropod from Late Cretaceous Russia, is described from the
Udurchukan Formation, (
Russia) by Averianov, Bolotsky, and Bolotsky (2023). •
Paul and Larramendi (2023) suggest that some sauropods reached sizes comparable to the largest whales, and propose that the fragmentary taxon
Bruhathkayosaurus may have weighed between 110 and 170 tonnes. • Multiple sauropod tracks assigned to
cf. Brontopodus isp., providing the first
ichnological evidence of gregarious behavior in Cretaceous sauropods in Africa, are described from the Lower Formation of the
Cenomanian Djoua series in the In Amenas region of
Algeria by Zaagane
et al. (2023).
Ornithischian research • A study on the biomechanical properties of the skulls of
Heterodontosaurus tucki,
Lesothosaurus diagnosticus,
Scelidosaurus harrisonii,
Hypsilophodon foxii and
Psittacosaurus lujiatunensis is published by Button
et al. (2023), who interpret their findings as indicative of limited functional convergence among studied taxa, which achieved comparable performance of the feeding apparatus through different adaptations. • A study on the evolution of forelimb muscle mechanics and function in ornithischian dinosaurs is published by Dempsey
et al. (2023), who interpret their findings as indicating that thyreophorans, ornithopods and ceratopsians evolved quadrupedality through different patterns of rearrangement of forelimb musculature. • Review of the fossil record of ornithischian dinosaurs from Southeast Asia and southern China is published by Manitkoon
et al. (2023) • Surmik
et al. (2023) study ossified tendons of specimens of
Pinacosaurus grangeri,
Edmontosaurus regalis/"
Ugrunaaluk kuukpikensis" and
Homalocephale calathocercos, reporting the presence of collagenous fibre bundles and likely fibril bundles, blood vessels and associated cells in some of the studied samples, and argue that ossified tendons can be a source of molecular preservation in dinosaurs. • A study on the histology and enamel microstructure of the maxillary cheek teeth of
Heterodontosaurus tucki, providing the earliest known evidence of the presence of wear-resistant modified dentine in an ornithischian, is published by Calvert
et al. (2023). • Description of the skull osteology of
Manidens condorensis is published by Becerra
et al. (2023). • Button &
Zanno (2023) present a three-dimensional endocranial reconstruction of a specimen of
Thescelosaurus neglectus, and report the presence of brain traits interpreted as suggestive of cognitive and behavioral capabilities within the range of extant reptiles, as well as a narrow hearing range, acute olfaction and
vestibular sensitivity which might represent adaptations for burrowing behaviors.
Thyreophoran research • A study on the phylogenetic relationships of thyreophorans is published by Raven
et al. (2023), who identify four distinct ankylosaur clades, with the long-standing clade Nodosauridae recovered as
paraphyletic; they suggest replacing the latter with the names
Panoplosauridae,
Polacanthidae, and
Struthiosauridae. • A study on the use of quadrapediality in
Scutellosaurus lawleri, and on its implications for locomotor behavior evolution in dinosaurs, is published by Anderson
et al. (2023), who interpret
Scutellosaurus as mainly being a biped, and suggest quadrapediality was used during specific activities. •
Galton (2023) describes a right sternal bone of a specimen of
Stegosaurus from the Carnegie Quarry at
Dinosaur National Monument (
Morrison Formation;
Utah,
United States) and reevaluates three putative sternal bones from
Como Bluff (
Wyoming, United States) described by
Gilmore (1914), arguing that they are neither sternal bones nor fossils of
Stegosaurus. • Description of
nodosaurid osteoderms from the Late Cretaceous
Snow Hill Island Formation (
Antarctica) is published by Brum
et al. (2023), who suggest that osteoderm structure may have helped nodosaurids colonize high-latitude environments more easily. • Yoshida, Kobayashi &
Norell (2023) report the discovery of fossilized larynx of a specimen of
Pinacosaurus grangeri from the Campanian of Ukhaa Tolgod (
Mongolia), and interpret its anatomy as indicating that
Pinacosaurus might have been capable of vocalization and, like extant birds, might have possessed a non-laryngeal vocal source and used larynx as a sound modifier. • Tumanova
et al. (2023) describe anomalies within the airway and sinuses of a skull of a specimen of
Tarchia, which were only detected while CT scanning the specimen, and which might have been caused by infection and/or trauma. • A study on the cranial biomechanics of
Panoplosaurus mirus and
Euoplocephalus tutus is published by Ballell, Mai &
Benton (2023), who find evidence of differences interpreted as indicative of relatively higher bite forces in
Panoplosaurus, as well as indicative of stronger reinforcement of the skull of
Euoplocephalus, consistent with highly defensive function.
Cerapod research • Evidence of significantly rougher dental microwear texture in Late Cretaceous
ornithopods compared to earlier members of the group, interpreted as indicative of dietary shift towards more abrasive foodstuffs, is presented by Kubo
et al. (2023). • Review of the diversity, relationships, biogeography and paleoecology of
rhabdodontids is published by Augustin, Ősi & Csiki-Sava (2023). • New rhabdodontid fossil material, possibly representing a taxon distinct from known Transylvanian rhabdodontids, is described from the Maastrichtian Densuș-Ciula Formation (Hațeg Basin;
Romania) by Magyar
et al. (2023). • Redescription of
Cumnoria prestwichii is published by
Maidment et al. (2023), who recover
Cumnoria as a non-
ankylopollexian
iguanodontian, and consider it to be distinct from
Camptosaurus. • Rotatori
et al. (2023) report the presence of a rich neurovascular network in the dentary of a
dryosaurid from the Upper Jurassic
Lourinhã Formation (
Portugal), similar to vascularisation present in
cerapodan dinosaurs with high tooth replacement rates. • Redescription of the
holotype of
Mantellisaurus atherfieldensis is published by Bonsor
et al. (2023), who confirm
Mantellisaurus to be distinct from
Iguanodon. • García-Cobeña, Cobosa & Verdú (2023) describe bone and trace fossils of
styracosternan ornithopods from the Lower Cretaceous
El Castellar Formation and
Camarillas Formation (
Spain), including
manus-
pes track set from the Camarillas Formation indicative of quadrupedal locomotion, assigned to the ichnogenus
Caririchnium and produced by large styracosternans related to
Iguanodon. • A study on the palynological sample from the matrix surrounding a specimen of
Iguanodon bernissartensis from the new Palau-3 site in the Lower Cretaceous
Morella Formation is published by Rodríguez-Barreiro
et al. (2023), who interpret the studied specimen as living in a coastal open forest environment with a warm and humid climate; the authors also compare the habitat of the studied specimen with those from other
I. bernissartensis-bearing sites, and interpret
I. bernissartensis as feeding mostly on fronds of ferns belonging to the families
Anemiaceae and
Cyatheaceae, as well as on the foliage of members of the family
Cheirolepidiaceae. • A study on the evolution of the dentary in hadrosauroids, providing evidence of changes during the transition from non-hadrosaurid hadrosauroids to saurolophids which probably enhanced food gathering and food processing abilities, is published by Söderblom
et al. (2023). • Description of new hadrosaurid fossils from the Upper Cretaceous
Kakanaut Formation (Chukotka,
Russia) and a study on their histology is published by Bapinaev
et al. (2023), who interpret the studied fossils as possibly indicative of the presence of two hadrosaurid taxa in the Kakanaut fauna, and interpret the histology of the studied bones as possibly indicating that Arctic hadrosaurids of Chukotka were year-round residents of polar ecosystems. • Joubarne, Therrien &
Zelenitsky (2023) describe extensive skin impressions in three hadrosaurid specimens from the
Campanian Dinosaur Park Formation (
Alberta,
Canada), with two specimens preserving integument of the
manus showing that their digits II–III–IV were approximately equal in length and united in a common fleshy structure, and the third specimen preserving scale stripes on its torso which might have corresponded to color stripes in life. • A study on the cranial suture interdigitation in Hadrosaurids, using data gathered from
Gryposaurus and
Corythosaurus is published by Dudgeon and Evans (2023) who find that suture interdigitation increased across Hadrosaurid
ontogeny, that Lambeosaurines had higher suture interdigitation than other Iguanodontians, and that increased suture complexity coincided with Lambeosaurine crest evolution. • Currie,
Lü & Wang (2023) describe the maxilla of a juvenile lambeosaurine (likely either
Corythosaurus or
Lambeosaurus) from the
Campanian Dinosaur Park Formation (Alberta, Canada), compare it with the maxilla of a probable juvenile hadrosaurine (possibly
Gryposaurus) from a different bonebed from the same formation, and interpret these fossils as indicating that lambeosaurines and hadrosaurines had similar tooth counts at hatching, which subsequently diverged during ontogeny. • Description of the anatomy of the postcranial skeleton of
Laiyangosaurus youngi is published by Zhang
et al. (2023). • Seymour
et al. (2023) estimate blood flow rates to the tibia shafts of
Maiasaura peeblesorum, and report higher flow rates in juveniles which were likely related to higher oxygen demand for bone growth in juveniles compared to maintenance and repair of bone tissue damage in adults. • A study on the anatomy of the
holotype specimen of
Gravitholus albertae is published by Dyer, Powers &
Currie (2023), who interpret both
Gravitholus albertae and
Hanssuesia sternbergi as likely
junior synonyms of
Stegoceras validum. • Han
et al. (2023) describe entangled specimens of
Psittacosaurus lujiatunensis and
Repenomamus robustus from the Lujiatun Member of the
Yixian Formation (
China), and interpret the studied specimens as likely locked in combat as a result of the predation attempt on the part of the mammal. • A study on the endocranial morphology of
Liaoceratops yanzigouensis is published by Yang
et al. (2023), who find that the brain, olfactory bulb and inner ear of
Liaoceratops more closely resemble those observed in
Psittacosaurus than those in more derived ceratopsians. • A review of the cranial evolution in
Ceratopsia is published by Nabavizadeh (2023). • Chiba
et al. (2023) provide evidence of the presence of frill margin undulations in
Protoceratops andrewsi, and interpret the undulated frill margin as possible shared feature in
protoceratopsids or even
Coronosauria. • Berry (2023) interprets the fossil record of late
Campanian ceratopsids from western North America as indicative of a significant rate of
background extinction approximately 76 million years ago, and interprets this pattern as most likely caused by competition for shared resources by
sympatric ceratopsid species. • The development and
homology of
epiparietals (P1 and P2) in three
Centrosaurus specimens are described by Mallon, Holmes & Rufolo (2023), who suggest that these are separate ossifications that fuse with the
parietal at different stages of
ontogeny. • A study on the bone histology of
Triceratops, providing evidence of a relatively fast and continuous growth rate, is published by de Rooij
et al. (2023). • A study on the range of shoulder motion and on the orientation of the long bones of the forelimb of
Thescelosaurus and
Styracosaurus is published by Senter & Mackey (2023). == Birds ==