2021 in archosaur paleontology

List of years in archosaur paleontology
… 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 …
In reptile paleontology 2018 2019 2020 2021 2022 2023 2024 In paleontology 2018 2019 2020 2021 2022 2023 2024 In science 2018 2019 2020 2021 2022 2023 2024
Art Archaeology Architecture Literature Music Philosophy Science +...

This article records new taxa of fossil archosaurs of every kind that are scheduled described during the year 2021, as well as other significant discoveries and events related to paleontology of archosaurs that are scheduled to occur in the year 2021.

General research

• A study on the relationship between full potential joint mobility and the poses used during locomotion in extant American alligator and helmeted guineafowl, evaluating its implications for reconstructions of locomotion of extinct archosaurs, is published by Manafzadeh, Kambic & Gatesy (2021).
• A study estimating moment arms for major pelvic limb muscles in extant and fossil archosaurs, aiming to investigate the idea that bird-line archosaurs switched from hip-based to knee-based locomotion between Archosauria (especially Neotheropoda) and Aves, is published by Allen, Kilbourne & Hutchinson (2021).
• A study aiming to determine how ontogenetic changes in skeletal anatomy influence muscle size, leverage, orientation, and locomotor function during the development of flight in extant chukar partridge is published by Heers et al. (2021), who evaluate the implications of their findings on current knowledge of how extinct winged theropods might have achieved bird-like behaviors before acquiring fully bird-like anatomies.
• A study on jumping mechanics and performance in extant elegant crested tinamou, and on its implications for inferences of jumping abilities in extinct animals such as dromaeosaurid dinosaurs, is published by Bishop et al. (2021).
• A study on the morphological diversity and evolution of the semicircular canals of the inner ear in extant and fossil archosaurs is published by Bronzati et al. (2021).
• A study on the evolution of eggshell thickness in non-avian dinosaurs and birds is published by Legendre & Clarke (2021).
• A study on the evolution of birdlike locomotor abilities and hearing acuity, as indicated by the anatomy of the inner ear in extant and fossil reptiles and birds, is published by Hanson et al. (2021).
• A study assessing the accuracy of bite force estimates in extinct archosaurs and mammals is published by Sakamoto (2021).

Pseudosuchians

Research

General

• A study on the phylogenetic relationships of pseudosuchian archosaurs, aiming to determine drivers of body size evolution in this group, is published by Stockdale & Benton (2021).
• The first occurrence of the track type "Chirotherium" lulli (inferred to be produced by a pseudosuchian archosaur) from western North America is reported from the Owl Rock Member of the Chinle Formation (Utah, United States) by Milner et al. (2021).

Aetosaurs

• Description of the braincase of Aetosauroides scagliai, based on data from specimens from the Upper Triassic Candelária Sequence (Brazil), is published by Paes Neto et al. (2021).
• An osteoderm of Typothorax coccinarum with punctures and scores which are likely bite marks is described from the Upper Triassic Chinle Formation (Arizona, United States) by Drymala, Bader & Parker (2021), who interpret this finding as supporting the hypothesis that aetosaurs were prey items of large archosauromorphs.
• Reyes, Parker & Marsh (2021) describe the first complete articulated skull of Typothorax coccinarum from the Owl Rock Member of the Chinle Formation (Petrified Forest National Park), and evaluate the implications of this specimen for the knowledge of the relationships and morphological diversity of aetosaurs.
• A study on the biomechanical properties of the skull of Neoaetosauroides engaeus is published by Taborda, Desojo & Dvorkin (2021).

Crocodylomorphs

• A study on the morphological diversity of skull and jaw shape in crocodylomorphs throughout their evolutionary history is published by Stubbs et al. (2021).
• A study on the evolution of the skull morphology in crocodyliforms is published by Felice, Pol & Goswami (2021).
• Description of coprolites from the Upper Cretaceous Adamantina Formation (Brazil) found in association with skeletons of baurusuchid and sphagesaurid crocodylomorphs, and a study on the implications of these coprolites for the knowledge of the diet of these crocodylomorphs, is published by de Oliveira et al. (2021).
• A study on the bone histology and growth dynamics of Araripesuchus, based on data from specimens from the La Buitrera Palaeontological Area (Río Negro Province, Argentina), is published by Fernández Dumont et al. (2021).
• A study on the resistance to stress of the skull of Araripesuchus gomesii, and on its implications for the knowledge of likely diet of this crocodylomorph, is published by Nieto et al. (2021).
• New partially preserved skull of Campinasuchus dinizi is described from the Fazenda São José (Adamantina/Vale do Rio do Peixe Formation, Brazil) by Darlim et al. (2021), who evaluate the implications of this specimen for the knowledge of the distribution of baurusuchids in the Late Cretaceous of South America.
• New soft tissue records for thalattosuchians are reported from the Late Jurassic localities of Wattendorf and Painten (Bavaria, Germany) by Spindler et al. (2021), who interpret their findings as indicating the skin of metriorhynchids lacked any traces of scales or scutes and instead showed folded and transverse fibers.
• Description of the cranial and endocranial anatomy of Macrospondylus bollensis is published by Wilberg et al. (2021).
• Isolated metriorhynchid tooth crowns, representing some of the most recent known occurrences of Metriorhynchidae worldwide, are described from the Valanginian Kopřivnice Formation (Czech Republic) by Madzia et al. (2021), who interpret these specimens as evidence of the presence of two distinct lineages of geosaurin metriorhynchids in the area of Czech Republic during the Early Cretaceous.
• A study on the anatomy of the braincase of a metriorhynchid specimen belonging or related to the species "Metriorhynchus" brachyrhynchus, and on the evolution of neurosensory and endocranial systems of metriorhynchids, is published by Schwab et al. (2021).
• A study on the anatomy of the snout of Dakosaurus andiniensis, and on the evolution of the facial anatomy of thalattosuchians, is published by Fernández & Herrera (2021), who interpret their findings as indicative of presence of anatomical adaptations likely helping drainage of nasal glands (probably excreting salt).
• A study on the evolution of tethysuchian and gavialoid crocodylomorphs from the Campanian to the Thanetian is published by Jouve (2021).
• A study on the anatomy of the braincase and inner ear of Rhabdognathus aslerensis is published by Erb & Turner (2021).
• A study on the anatomy of the postcranial skeleton of Cerrejonisuchus improcerus is published by Scavezzoni & Fischer (2021), who also provide new information on the anatomy of the postcranial skeletons of Congosaurus bequaerti and Hyposaurus rogersii, and provide evidence of a distinctive postcranial anatomy of dyrosaurids among crocodyliforms.
• New fossil material of Deltasuchus motherali, providing new information on changes in the skeleton of this crocodyliform during the ontogeny, and indicative of dietary shifts from juvenile to adult, is described from the Cenomanian Woodbine Formation (Texas, United States) by Drumheller et al. (2021), who also study the phylogenetic relationships of D. motherali, and identify an endemic clade of Appalachian crocodyliforms, which they name Paluxysuchidae.
• New fossil material of Deinosuchus, representing one of the earliest records of this genus in North American reported to date, is described from the Campanian Menefee Formation (New Mexico, United States) by Mohler, McDonald & Wolfe (2021).
• Description of the crocodyliform fossil material from the Eocene (Lutetian) Ikovo locality (Ukraine), including the easternmost record of diplocynodontines in Europe reported to date, is published by Kuzmin & Zvonok (2021), who also review the fossil record and biogeography of crocodyliforms from the Paleocene and Eocene of Europe.
• Cidade & Rincón (2021) report the first occurrence of Acresuchus pachytemporalis from the Miocene Urumaco Formation (Venezuela), expanding known geographic distribution of this species.
• Description and a study on the taxonomic status of the crocodylians from the Neogene Irrawaddy Formation (Myanmar), including one of the oldest records of the genus Gavialis reported to date, is published by Iijima et al. (2021).
• Revision of the taxonomy and a study on the phylogenetic relationships of the Miocene tomistomines from Italy and Malta is published by Nicholl et al. (2021).
• A study on the phylogenetic relationships of Voay robustus, based on mitochondrial genomic data, is published by Hekkala et al. (2021).
• Description of a new skull of Crocodylus anthropophagus from the DK site at Olduvai (Tanzania), representing the oldest fossil of a member of this species reported to date, and a study on the phylogenetic relationships of this species is published by Azzarà et al. (2021)

New taxa

Name	Novelty	Status	Authors	Age	Type locality	Country	Notes	Images
Allodaposuchus iberoarmoricanus	Sp. nov	Valid	Blanco	Late Cretaceous (Campanian)		France
Aphaurosuchus	Gen. et sp. nov	Valid	Darlim, Montefeltro & Langer	Late Cretaceous (Campanian-Maastrichtian)	Bauru Basin	Brazil	A baurusuchid crocodylomorph. Genus includes new species A. escharafacies.
Brachiosuchus	Gen. et sp. nov	In press	Salih et al.	Late Cretaceous	Kababish Formation	Sudan	A dyrosaurid crocodylomorph. Genus includes new species B. kababishensis.
Burkesuchus	Gen. et sp. nov	Valid	Novas et al.	Late Jurassic (Tithonian)	Toqui Formation	Chile	An early member of Mesoeucrocodylia. The type species is B. mallingrandensis.
Caipirasuchus attenboroughi	Sp. nov	Valid	Ruiz et al.	Late Cretaceous (Turonian-Campanian)	Santo Anastácio Formation	Brazil	A sphagesaurid crocodylomorph.
Chinatichampsus	Gen. et sp. nov	Valid	Stocker, Brochu & Kirk	Eocene (Uintan-Duchesnean)	Devil's Graveyard Formation	United States (Texas)	A caiman. The type species is C. wilsonorum.
Coronelsuchus	Gen. et sp. nov	Valid	Pinheiro et al.	Late Cretaceous (Turonian)	Araçatuba Formation	Brazil	A sphagesaurian crocodylomorph. The type species is C. civali
Cricosaurus albersdoerferi	Sp. nov	Valid	Sachs, Young, Abel, & Mallison	Late Jurassic (Kimmeridgian)	Torleite Formation	Germany
Cricosaurus rauhuti	Sp. nov	Valid	Herrera, Aiglstorfer & Bronzati	Late Jurassic (Tithonian)	Mörnsheim Formation	Germany
Gunggamarandu	Gen. et sp. nov	Valid	Ristevski et al.	Pliocene or Pleistocene		Australia	A tomistomine crocodylian. The type species is G. maunala.
Kocurypelta	Gen. et sp. nov	Valid	Czepiński et al.	Late Triassic (Norian)	Lissauer Breccia	Poland	An aetosaur. Genus includes new species K. silvestris.

Non-avian dinosaurs

Research

General

• A study on the impact of the disparity between neonates and adults on the structure and diversity of dinosaur communities is published by Schroeder, Lyons & Smith (2021), who claim that communities with giant theropods lacked carnivores weighing 100 to 1000 kg, and argue that juveniles of giant theropod species likely filled the mesocarnivore niche, resulting in reduced overall taxonomic diversity.
• Evidence of cessation of longitudinal skeletal growth in non-avian dinosaurs, inferred from a study of the articular surfaces of long bones, is presented by Rothschild & Witzmann (2021).
• A study aiming to determine whether the presence of keratan sulfate is exclusive evidence for the presence of medullary bone in dinosaur fossils (and therefore whether it can be used to identify dinosaur specimens as gravid females) is published by Canoville et al. (2021).
• A study on the variation in tail anatomy and length across the Dinosauria is published by Hone, Persons & Le Comber (2021).
• A study on the possibilities of determination of the presence of sexual dimorphism in dinosaurs, evaluating whether the previous method used for dinosaurs correctly recognizes living animals as dimorphic, is published by Motani (2021).
• Review of the fossil record of Carnian dinosaurs from South America is published by Novas et al. (2021), who also interpret Chindesaurus, Daemonosaurus and Tawa as likely late-surviving members of Herrerasauria.
• A study on dinosaur trackways that show changes in direction from Jurassic and Cretaceous sites in North and South America, Europe and Asia is published by Lockley et al. (2021).
• Fossil trackways made by theropods, ornithopods and possibly ankylosaurs, are reported from the Folkestone Formation of the Lower Greensand Group by Hadland et al (2021), representing the youngest known footprints of non-avian dinosaurs known from the United Kingdom.
• A study on the climate of the Lufeng area (China) during the Early Jurassic, and on the relationship between the global distribution of dinosaur fossils and climate during the Jurassic, is published by Shen et al. (2021).
• Druckenmiller et al. (2021) report the discovery of a diverse assemblage of herbivorous and carnivorous non-avian dinosaurs, including perinatal and very young specimens, from the Upper Cretaceous Prince Creek Formation (Alaska, United States), and interpret this finding as indicating that most, if not all, dinosaurs from this assemblage were nonmigratory year-round Arctic residents.
• A study on the distribution of dinosaurs across the latest Cretaceous of North America is published by García‐Girón et al. (2021).
• A study aiming to determine whether plant-eating dinosaurs could have moved seeds long distances is published by Perry (2021).
• A study on changes of diversity of dinosaurs belonging to the families Ankylosauridae, Ceratopsidae, Hadrosauridae, Dromaeosauridae, Troodontidae and Tyrannosauridae during the Late Cretaceous is published by Condamine et al. (2021), who interpret their findings as indicative of a decline of non-avian dinosaur diversity during the last 10 million years of the Cretaceous period, and attempt to determine possible causes of this decline.

Saurischians

• New fossil material of theropod and sauropod dinosaurs, including a caudal vertebra with pneumatic internal structures rarely observed outside Late Cretaceous South American saltasaurines, is described from the Campanian Quseir Formation (Egypt) by Salem et al. (2021).
• Putative large-sized sauropodomorph specimen from the Carnian strata at the ‘Cerro da Alemoa’ locality (southern Brazil) is reinterpreted as a herrerasaurid specimen (the largest dinosaur reported from the Candelária Sequence to date) by Garcia et al. (2021).

Theropods

• A study aiming to determine whether the knowledge of patterns of species abundance and clade diversity in theropod dinosaurs is significantly impacted by the diagnosability of their fossils is published by Cashmore, Butler & Maidment (2021).
• A study on the evolution of vision and hearing modalities in theropod dinosaurs is published by Choiniere et al. (2021), who interpret their findings as indicative of early evolution of nocturnal predation in alvarezsauroid theropods.
• A vertebra of a non-coelophysoid, non-averostran neotheropod which may be 15 million years older than Dilophosaurus wetherilli is described from the Lower Jurassic (Hettangian) Whitmore Point Member of the Moenave Formation (Utah, United States) by Marsh et al. (2021), who interpret this finding as indicating that not all contemporaneous theropod traces were made by coelophysoids.
• New fossil material of ceratosaur theropods, probably representing one of the oldest known record of abelisaurids, is described from the Upper Jurassic Cañadón Calcáreo Formation (Argentina) by Rauhut & Pol (2021).
• A study on the skeletal anatomy and phylogenetic relationships of Xenotarsosaurus bonapartei is published by Ibiricu et al. (2021).
• Spinosaurid neck vertebrae distinct from known vertebrae of Spinosaurus aegyptiacus and exhibiting an unusual combination of positionally variable characters are described from the Kem Kem Group (Morocco) by McFeeters (2021), who interprets this finding as evidence of a greater degree of intraspecific variation in the vertebrae of S. aegyptiacus than previously recognized, or alternatively, evidence for the occurrence of two spinosaurid taxa in the Kem Kem Group.
• Spinosaurid caudal vertebrae are described from the Lower Cretaceous Sao Khua Formation (Thailand) by Samathi, Sander & Chanthasit (2021), who also reinterpret the putative ceratosaur Camarillasaurus cirugedae as a spinosaurid.
• Hone & Holtz (2021) evaluate the evidence for the competing interpretations of the ecology of Spinosaurus, and reject the interpretation of this theropod as a specialised aquatic pursuit predator.
• A study on the histology and geochemistry of a tibia and a femur of a specimen or specimens of Allosaurus fragilis from the Cleveland-Lloyd Dinosaur Quarry (Utah, United States), and on its implications for the knowledge of the growth strategy of this species, is published by Ferrante et al. (2021).
• Caudal vertebra of a theropod with affinities to Carcharodontosauria is described from the Upper Jurassic Sergi Formation by Bandeira et al. (2021), representing the first unambiguous record of a dinosaur from the Jurassic of Brazil reported to date.
• A study on the phylogenetic affinities of putative carcharodontosaurid teeth from the Upper Cretaceous strata in northern and central Patagonia, and on their implications for the knowledge of the timing of extinction of carcharodontosaurids in South America, is published by Meso et al. (2021).
• A study on the skeletal anatomy of Aerosteon riocoloradensis is published by Aranciaga Rolando et al. (2021).
• Fragmentary specimens of tyrannosaurid theropods from the Dinosaur Park Formation of the Alberta, Canada) in the collection of the San Diego Natural History Museum were described by Yun (2021).
• Bones of tyrannosaurid theropods with extensive tooth marks matching the teeth of tyrannosaurids are described from the Upper Cretaceous of the San Juan Basin (northwestern New Mexico, United States) by Dalman & Lucas (2021), who interpret this finding as evidence for cannibalistic behavior among tyrannosaurids.
• Caneer, Moklestad & Lucas (2021) describe structures which are not readily assignable to any known ichnotaxon from the Upper Cretaceous of the Raton Basin (New Mexico), and interpret them as one footprint and two forearm/hand prints probably produced by a large tyrannosaurid theropod standing up from a prone position.
• Perinatal tyrannosaurid bones and teeth are described from the Upper Cretaceous Two Medicine Formation (Montana, United States) and Horseshoe Canyon Formation (Alberta, Canada) by Funston et al. (2021), who evaluate the implications of these findings for the knowledge of the minimum hatchling size of tyrannosaurids, their nesting habits and development of their teeth.
• A study on tyrannosaurid tracks from the Campanian Wapiti Formation (Alberta, Canada), evaluating the implications of these tracks for the knowledge of changes in pedal anatomy of tyrannosaurids during their ontogeny, is published by Enriquez et al. (2021).
• A study on possible causes of monopolization of large carnivore guilds in Asian and American dinosaur assemblages by tyrannosaurids in the latest Cretaceous is published by Holtz (2021).
• A study on changes of mandibular biomechanical properties and tooth morphology in Albertosaurus sarcophagus and Gorgosaurus libratus during their ontogeny is published by Therrien et al. (2021), who interpret their findings as indicating the occurrence of ontogenetic dietary shift in albertosaurine tyrannosaurids.
• A study on the mechanical properties of the mandibles of tyrannosaurine tyrannosaurids representing different ontogenetic stages (including small juvenile) is published by Rowe & Snively (2021).
• New bone bed containing at least four specimens of Teratophoneus curriei or a related tyrannosaurid is described from the Campanian Kaiparowits Formation (Utah, United States) by Titus et al. (2021), who study the taphonomy of this bone bed, and evaluate its implications for the knowledge whether known accumulations of tyrannosaurid specimens represent time-averaged or forced accumulations, or whether they are evidence of gregariousness of tyrannosaurids.
• A metatarsal of juvenile tyrannosaurid theropod from the Dinosaur Park Formation of the Alberta, Canada, possibly referable to Daspletosaurus torosus was described by Yun (2021).
• A study aiming to calculate population variables such as abundance at any one time, species persistence and total number of individuals that ever lived for Tyrannosaurus rex is published by Marshall et al. (2021).
• A study aiming to estimate the natural frequency of the vertical swaying of the tail and the preferred walking speed and step frequency of Tyrannosaurus rex is published by van Bijlert, van Soest & Schulp (2021).
• A study attempting to determine bite force of a juvenile Tyrannosaurus rex, based on mechanical tests designed to replicate bite marks attributed to juvenile specimens of this species, is published by Peterson, Tseng & Brink (2021).
• A study on the anatomy of the postcranial skeleton and on the phylogenetic relationships of Pelecanimimus polyodon is published by Cuesta et al. (2021), who name a new clade Macrocheiriformes, defined as Pelecanimimus and all derived ornithomimosaurs.
• A study on pelvic musculature in non-avian maniraptorans is published by Rhodes, Henderson & Currie (2021).
• A study on the neuroanatomy of a new alvarezsauroid skeleton in the collection of the Henan Geological Museum (China) is published by Agnolín et al. (2021).
• A study on the skeletal anatomy, probable musculature and likely function of tails of alvarezsaurian theropods is published by Meso et al. (2021).
• A study on growth strategies and body miniaturization in the evolutionary history of alvarezsauroid theropods is published by Qin et al. (2021).
• Reconstructions of the muscular system of the hindlimb, forelimb and the shoulder girdle of Nothronychus are presented by Smith (2021).
• Partial skeleton of Elmisaurus rarus, preserving elements overlapping with known fossil material of Nomingia gobiensis, is described from the Upper Cretaceous Nemegt Formation (Mongolia) by Funston et al. (2021), who interpret this specimen as indicating that N. gobiensis is likely a junior synonym of E. rarus.
• Cau et al. (2021) report the identification of additional elements of the pectoral apparatus of the holotype specimen of Halszkaraptor escuilliei, including the furcula, and evaluate its implications for the knowledge of the evolution of the avian furcula.
• A study on the anatomy of the skeleton of Unenlagia comahuensis is published by Novas et al. (2021).
• A study on the vertebral pneumaticity in Unenlagia comahuensis is published by Gianechini & Zurriaguz (2021).
• Description of a new troodontid specimen from the Upper Cretaceous Wulansuhai Formation (China), and a study on the phylogenetic relationships and evolutionary history of the Late Cretaceous troodontids, is published by Wang et al. (2021).
• Multi-individual aggregates of mammal skeletons are described from the Upper Cretaceous Two Medicine Formation (Montana, United States) by Freimuth et al. (2021), who interpret these aggregates as the oldest known mammal-bearing regurgitalites, probably produced by Troodon formosus.
• Brown, Tanke & Hone (2021) describe a hadrosaurid bone from the Campanian Dinosaur Park Formation (Alberta, Canada) preserved with bite marks produced by a small- to medium-sized theropod dinosaur, deviating from the majority of known theropod tooth marks and indicative of a behavior similar to mammalian gnawing.
• Revision of the biodiversity of theropods from the Dinosaur Park Formation is published by Cullen et al. (2021).
• Exquisitely preserved, ornamented partial eggs with theropod affinities, representing some of the smallest Mesozoic eggs reported to date, are described from the Campanian Kaiparowits Formation (Utah, United States) by Oser et al. (2021), who name a new ootaxon Stillatuberoolithus storrsi.

Sauropodomorphs

• Review of the diversity and composition of South American sauropodomorph faunas throughout the Late Triassic is published by Pol et al. (2021).
• A study on the evolution of the olfactory system in sauropodomorph dinosaurs, as indicated by the ratio between the size of the olfactory bulbs and cerebral hemispheres in sauropodomorph endocasts, is published by Müller (2021).
• A study on the timing of the earliest occurrence of Triassic sauropodomorphs in their northernmost range (Fleming Fjord Formation, Greenland), and on possible relationship between climate changes and early sauropodomorph dispersal to the temperate belt of the Northern Hemisphere, is published by Kent & Clemmensen (2021).
• New skull material of Plateosaurus, including the first two juvenile skulls of members of this genus, is described from the locality of Frick (Switzerland) by Lallensack et al. (2021), who attempt to determine whether the locality of Frick and German localities of Trossingen and Halberstadt contain specimens of Plateosaurus belonging to a single species.
• A study on the skeletal growth during the ontogeny in Massospondylus carinatus is published by Chapelle, Botha & Choiniere (2021).
• A study on the cranial anatomy of Anchisaurus polyzelus and the development of cranial characters in sauropodomorph ontogeny is published by Fabbri et al. (2021)
• An extensive Late Jurassic sauropod tracksite, preserving the longest continuous sequence of sauropod pes prints reported to date and representing a rare record of a >180° turn made by the sauropod trackmaker to completely change direction and cross its own trackway, is described from a high altitude locality near Ouray (Colorado, United States) by Goodell et al. (2021).
• A study on the skeletal anatomy of the holotype of Patagosaurus fariasi is published by Holwerda, Rauhut & Pol (2021).
• A new specimen of Haplocanthosaurus with expanded neural canals is described by Wedel et al. (2021).
• A study on the anatomy and phylogenetic relationships of Amphicoelias altus is published by Mannion, Tschopp & Whitlock (2021).
• The paleohistology of two dicraeosaurids from the La Amarga Formation (Argentina) is studied by Winholdz and Cerda (2021), who find that the holotype specimen of Amargatitanis macni belonged to a more mature individual than the holotype of Amargasaurus cazaui.
• Fossilized skin of a juvenile member of the genus Diplodocus, providing evidence of new scale shapes and patterns never before seen in diplodocids, is described from the Mother's Day Quarry (Bighorn Basin, Montana, United States) by Gallagher, Poole & Schein (2021).
• Redescription of the anatomy of the braincase of Limaysaurus tessonei is published by Paulina-Carabajal & Calvo (2021).
• Description of the anatomy of the referred specimen of Diamantinasaurus matildae and a study on the phylogenetic relationships of this species is published by Poropat et al. (2021), who name a new clade Diamantinasauria, which includes it alongside Savannasaurus and Sarmientosaurus.
• Fossil material of a giant titanosaur sauropod, distinct from Andesaurus and probably exceeding Patagotitan in size, is described from the Cenomanian Candeleros Formation (Argentina) by Otero et al. (2021).
• Revision of known fossil material of Pellegrinisaurus powelli and a study on the skeletal anatomy, bone histology and phylogenetic relationships of this sauropod are published by Cerda et al. (2021).
• New titanosaur remains, possibly belonging to a member of Colossosauria distinct from previously known taxa, are described from the Upper Cretaceous Portezuelo Formation (Argentina) by Bellardini et al. (2021).
• A study on the composition of several gastroliths from the Morrison are published by Malone, Strasser, Malone, D’Emic, Brown, and Craddock, who point to the differences between them and the surrounding rock and similarities to another site 1,000 km eastwards to suggest evidence of migration in sauropod dinosaurs.
• Description of new fossil material and a study on the phylogenetic relationships of Tengrisaurus starkovi is published by Averianov, Sizov & Skutschas (2021).
• Evidence of the preservation of nitrogen-bearing organic molecules (identified as proteinaceous moieties) in titanosaur eggshell from the Maastrichtian Lameta Formation (India) is presented by Dhiman et al. (2021).
• A study on the stable isotope compositions of titanosaurian eggshells, bone and an associated tooth sampled in three Late Cretaceous nesting sites from La Rioja Province (Argentina), evaluating their implications for the knowledge of the body temperature of titanosaur sauropods, their diet, and the environmental conditions they needed reproduce, is published by Leuzinger et al. (2021).

Ornithischians

• New fossil material of ornithischians, including remains of basal euiguanodontian and hadrosaurid ornithopods and the southernmost record of ankylosaurs from South America reported to date, is described from the Upper Cretaceous (Campanian–Maastrichtian) Chorrillo Formation (Argentina) by Rozadilla et al. (2021), who evaluate the implications of these fossils for the knowledge of the evolutionary history of ankylosaurs and hadrosaurids in South America.
• Radermacher et al. (2021) describe a new, fully articulated skeleton of Heterodontosaurus tucki, preserving a suite of novel postcranial features unknown in any other ornithischian dinosaur, and evaluate the implications of this specimen for the knowledge of the evolution of ornithischian respiratory biology.

Thyreophorans

• A study on the skeletal anatomy and bone histology of Scutellosaurus lawleri, providing new data on the morphology and new life reconstruction for this dinosaur, is published by Breeden et al. (2021).
• A stegosaurian humerus is described from the Cañadón Calcáreo Formation (Argentina) by Rauhut, Carballido & Pol (2021), extending the fossil record of Stegosauria to the Late Jurassic of South America.
• A study on the morphology, macro- and microwear, and microanatomy of the stegosaur teeth from the Teete locality (Lower Cretaceous Batylykh Formation; Sakha, Russia), evaluating their implications for the knowledge of the paleobiology of the Teete stegosaur, is published by Skutschas et al. (2021).
• The smallest stegosaur track reported to date, co-occurring with the tracks of larger individuals, is described from the Lower Cretaceous Tugulu Group (Xinjiang, China) by Xing et al. (2021).
• Riguetti et al. (2021) describe nodosaurid tracks from the Maastrichtian El Molino Formation (Bolivia), increasing known diversity of ankylosaur tracks from South America.
• Several fragmentary skulls and skull elements of Hungarosaurus, providing new information on the morphological diversity, development and possible function of the ornamentation of nodosaurid skulls, are described by Ősi et al. (2021).
• A study on dental microwear and jaw movement of Jinyunpelta, and on its implications for the knowledge of the evolution of the feeding mechanism of ankylosaurids, is published by Kubo et al. (2021).
• Articulated postcranial skeleton of an indeterminate ankylosaurid dinosaur is described from the Barun Goyot Formation (Mongolia) by Park et al. (2021), who interpret this specimen as indicating that Asian ankylosaurids evolved rigid bodies with a reduced number of pedal phalanges, as well as the existence of at least two forms of flank armor in ankylosaurids, and discuss possible adaptations for digging in ankylosaurids.

Cerapods

• A study on the skeletal anatomy and phylogenetic relationships of Haya griva is published by Barta & Norell (2021).
• A study on the anatomy of the manus of Tenontosaurus tilletti is published by Hunt, Cifelli & Davies (2021).
• A study on the accumulated remains of Dysalotosaurus lettowvorbecki from the Upper Jurassic Tendaguru Formation (Tanzania) is published by Hübner et al. (2021), who interpret two large bonebeds as most likely resulting from two independent catastrophic mortality events.
• A study on the anatomy of the braincase and probable brain size in Proa valdearinnoensis is published by Knoll et al. (2021).
• A specimen of Gobihadros mongoliensis preserving features of cessation of growth, indicating that it reached the terminal size and advanced age, is described from the Upper Cretaceous Bayan Shireh Formation (Mongolia) by Słowiak et al. (2021), who diagnose this specimen as affected by calcium pyrophosphate deposition disease, making it the first known non-avian dinosaur specimen affected with this disease.
• Redescription of the anatomy and a study on the phylogenetic relationships of Lophorhothon atopus, based on data from the holotype and from a new specimen, is published by Gates & Lamb (2021).
• A study on the anatomy of the postcranial skeleton of Tanius sinensis is published by Borinder et al. (2021).
• Description of new fossil material of hadrosaurids from the Upper Cretaceous Lago Colhué Huapí Formation (Argentina), and a study on the environment inhabited by these hadrosaurids and on the influence of paleoenvironmental conditions on South American hadrosaurid distribution, is published by Ibiricu et al. (2021).
• Holland et al. (2021) describe an assemblage of late juvenile hadrosaurid specimens from the Spring Creek Bonebed (Alberta, Canada), representing the first record of lambeosaurines from the Wapiti Formation and possibly indicating that age segregation was a life history strategy among hadrosaurids.
• Revision of the type material and a study on the phylogenetic affinities of Latirhinus uitstlani is published by Ramírez-Velasco, Espinosa-Arrubarrena & Alvarado-Ortega (2021).
• Redescription of Parasaurolophus cyrtocristatus, based on data from a new skull from the Campanian Fruitland Formation (New Mexico, United States), is published by Gates, Evans & Sertich (2021).
• A study on the injuries of the holotype specimen of Bonapartesaurus rionegrensis, and on their implications for the knowledge of its paleobiology, is published by Cruzado-Caballero et al. (2021).
• A study aiming to determine the taxonomic validity of the species Sphaerotholus buchholtzae and S. edmontonensis is published by Woodruff et al. (2021).
• Vinther, Nicholls & Kelly (2021) describe the first fossil cloacal vent in an exceptionally preserved non-avian dinosaur specimen (a specimen of Psittacosaurus from the Early Cretaceous Jehol deposits of Liaoning, China).
• A study on jaws and teeth of juvenile and adult specimens of Psittacosaurus lujiatunensis, aiming to determine whether this dinosaur underwent a dietary shift during its ontogeny, is published by Landi et al. (2021).
• A study on the ontogenetic changes in the femoral histology of Psittacosaurus sibiricus is published by Skutschas et al. (2021).
• A study on the whole-skull shape in a large sample of specimens of Protoceratops andrewsi is published by Knapp, Knell & Hone (2021), who argue that the frill of P. andrewsi shows several characteristics consistent with a socio-sexual trait.
• A study on the biodiversity patterns of Late Cretaceous hadrosaurids and ceratopsids from the western interior of North America, evaluating whether the fossil record provides evidence of faunal provinciality of these dinosaurs, is published by Maidment et al. (2021).

New taxa

Name	Novelty	Status	Authors	Age	Type locality	Country	Notes	Images
Arackar	Gen. et sp. nov	Valid	Rubilar-Rogers et al.	Late Cretaceous (Campanian–Maastrichtian)	Hornitos Formation	Chile	A lithostrotian titanosaur sauropod. Genus includes new species A. licanantay.
Arrudatitan	Gen. et comb. nov	Valid	Silva Junior et al.	Late Cretaceous (Campanian-Maastrichtian)	Adamantina Formation	Brazil	A titanosaur sauropod; a new genus for "Aeolosaurus" maximus.
Australotitan	Gen. et sp. nov	Valid	Hocknull et al.	Late Cretaceous (Cenomanian-? Turonian)	Winton Formation	Australia	A titanosaur sauropod. The type species is A. cooperensis.
Dzharatitanis	Gen. et sp. nov	Valid	Averianov & Sues	Late Cretaceous (Turonian)	Bissekty Formation	Uzbekistan	A sauropod of uncertain phylogenetic placement. Originally described as a rebbachisaurid, but subsequently argued to be a member of Titanosauria. The type species is D. kingi.	File:Dzharatitanis kingi restoration.jpg
Fylax	Gen. et sp. nov	Valid	Prieto-Márquez and Carrera Farias	Late Cretaceous (Maastrichtian)	Figuerola Formation	Spain	A non-hadrosaurid hadrosauromorph. The type species is F. thyrakolasus.
Kansaignathus	Gen. et sp. nov	Valid	Averianov and Lopatin	Late Cretaceous (Santonian)	Ialovachsk Formation	Tajikistan	A velociraptorin dromaeosaurid. The type species is K. sogdianus.
Llukalkan	Gen. et sp. nov	Valid	Gianechini et al.	Late Cretaceous (Santonian)	Bajo de la Carpa Formation	Argentina	A furileusaurian abelisaurid. The type species is L. aliocranianus.
Menefeeceratops	Gen. et sp. nov	Valid	Dalma et al.	Late Cretaceous (Campanian)	Menefee Formation	United States (New Mexico)	A centrosaurine ceratopsid, possibly a member of the tribe Nasutoceratopsini. The type species is M. sealeyi.
Ninjatitan	Gen. et sp. nov	Valid	Gallina, Canale, & Carballido	Early Cretaceous (Berriasian–Valanginian)	Bajada Colorada Formation	Argentina	The earliest known titanosaur sauropod found. The type species is N. zapatai.
Ornatops	Gen. et sp. nov	Valid	McDonald et al.	Late Cretaceous (Campanian)	Menefee Formation	United States (New Mexico)	A saurolophine hadrosaurid belonging to the tribe Brachylophosaurini. The type species is O. incantatus.	File:Ornatops.jpg
Portellsaurus	Gen. et sp. nov	Valid	Santos-Cubedo et al.	Early Cretaceous (Barremian)	Margas de Mirambell Formation	Spain	A styracosternan hadrosauroid. The type species is P. sosbaynati
Shri	Gen. et sp. nov	Valid	Turner, Montanari & Norell	Late Cretaceous (Maastrichtian)	Barun Goyot Formation	Mongolia	A dromaeosaurid theropod. Genus includes new species S. devi.
Tamarro	Gen. et sp. nov	Valid	Sellés et al.	Late Cretaceous (Maastrichtian)	Talarn Formation	Spain	A troodontid theropod. The type species is T. insperatus.
Tlatolophus	Gen. et sp. nov	Valid	Ramírez-Velasco et al.	Late Cretaceous (Campanian)	Cerro del Pueblo Formation	Mexico	A lambeosaurine hadrosaurid belonging to the tribe Parasaurolophini. Genus includes new species T. galorum.
Yamatosaurus	Gen. et sp. nov	Valid	Kobayashi et al.	Late Cretaceous (Maastrichtian)	Kita-Ama Formation	Japan	A basal hadrosaurid. The type species is Y. izanagii.
Ypupiara	Gen. et sp. nov	In press	Brum et al.	Late Cretaceous (Maastrichtian)	Marília Formation	Brazil	An unenlagiin dromaeosaurid. The type species is Y. lopai.

Birds

Research

• The study on the phylogenetic relationships and powered flight potential of early birds and their closest relatives published by Pei et al. (2020), arguing that the potential for powered flight evolved at least three times (once in birds and twice in dromaeosaurids), is criticized by Serrano & Chiappe (2021).
• A study on the diversification rates of birds throughout their evolutionary history is published by Yu, Zhang & Xu (2021).
• A study on the evolution of the brain in birds, based on data from extant and recently extinct birds, Archaeopteryx and non-avian coelurosaurian theropods, is published by Watanabe et al. (2021).
• A study aiming to infer the diets of the last common ancestor of living birds, based on data from digestive system-related genes, is published by Wu (2021), who interprets his findings as indicative of a diet shift from carnivory to herbivory at the non-avian archosaur-to-bird transition, and evaluates possible implications of this diet shift for the evolution of early birds.
• Review of methods used to determine diet in modern and fossil birds, evaluating their utility for determination of diets of Mesozoic birds, is published by Miller & Pittman (2021).
• A study on patterns and modes of the evolution of skeletal morphology and limb proportions in Mesozoic birds is published by Wang et al. (2021).
• A study on the variation in tooth crown shape of Mesozoic birds, and its implications for the knowledge of their diets, is published by Zhou et al. (2021).
• A study on the impact of tooth loss on the diversification of Mesozoic birds is published by Brocklehurst & Field (2021), who find no evidence for a link between toothlessness and accelerated cladogenesis, as well as no evidence for models whereby acquisitions of toothlessness among Mesozoic birds were driven by an overarching selective trend.
• Review of the variability of bone histology in basal members of Avialae is published by Monfroy & Kundrát (2021).
• A study on the ecomorphology of extant and fossil birds, aiming to determine whether the ecologies of Mesozoic birds can be inferred on the basis of data from measurements of their forelimbs and hindlimbs, is published by Bell et al. (2021).
• The study published by Kaye, Pittman & Wahl (2020), reporting evidence interpreted by the authors as indicative of the feather moulting in the Thermopolis specimen of Archaeopteryx, is criticized by Kiat et al. (2021).
• A study on the histology of the scapulocoracoid in Confuciusornis is published by Wu et al. (2021).
• New enantiornithine specimen with a well-preserved skull, retaining the plesiomorphic dinosaurian palate and diapsid temporal configurations indicative of an akinetic skull, is described from the Lower Cretaceous Jiufotang Formation (China) by Wang et al. (2021), who evaluate the implications of this specimen for the knowledge of the evolution of bird skulls.
• A study on the anatomy of the quadrate bone of Longipteryx chaoyangensis, evaluating its possible functional implications, is published by Stidham & O'Connor (2021).
• A study on the identity of purported gastroliths reported in a referred specimen of Bohaiornis guoi from the Early Cretaceous of China is published by Liu et al. (2021).
• A study on the bone histology and growth of the skeleton of Mirarce eatoni is published by Atterholt et al. (2021).
• An almost complete juvenile specimen of Archaeorhynchus is described from the Aptian Jiufotang Formation (China) by Foth et al. (2021), who evaluate the implications of the anatomy of this specimen for the knowledge of the ontogenetic development of Mesozoic birds.
• Ju et al. (2021) revise the fossil material of Iteravis huchzermeyeri and Gansus zheni, and consider these species to be synonymous.
• A cervical vertebra of a member of Ornithuromorpha distinct from Gargantuavis, representing the first fossil evidence of a giant bird from the late Maastrichtian of Europe reported to date, is described from Beranuy (Huesca, Spain) by Pérez-Pueyo et al. (2021).
• Torres, Norell & Clarke (2021) describe a new specimen of Ichthyornis dispar from the Niobrara Formation (Kansas, United States), preserving a nearly complete skull, and evaluate the implications of the anatomy of this specimen for the knowledge of the evolution of birds and for the knowledge of probable reasons why birds survived the end-Cretaceous mass extinction.
• New information on the anatomy of Vegavis iaai, based on data from the holotype specimen which was fully extracted from the sedimentary matrix, is presented by Acosta Hospitaleche & Worthy (2021).
• Mayr & Zelenkov (2021) interpret eogruids and ergilornithids as representatives of the stem group of Struthioniformes, based on data from new fossils from the late Eocene of Mongolia.
• A fossil ostrich specimen with exceptional soft-tissue preservation is described from the Miocene Liushu Formation (Linxia Basin, China) by Li et al. (2021).
• A femur of a giant ostrich, significantly larger than the living common ostrich, is described from the Pleistocene Nihewan Formation (China) by Buffetaut & Angst (2021), who assign it to Pachystruthio indet. and interpret this finding as evidence of wide geographical distribution of giant ostriches in the Early Pleistocene of Eurasia.
• A mid-Holocene coprolite deposit attributed to the bush moa is reported from southern New Zealand by Wood et al. (2021), who evaluate the implications of this finding for the knowledge of the diet and ecology of this moa.
• A study comparing egg size and volume in extinct island emus and in mainland emu, aiming to determine egg size in relation to body size in island emus and their breeding strategy, is published by Hume & Robertson (2021).
• A study on the phylogenetic relationships of Brontornis burmeisteri is published by Agnolin (2021), who interprets this taxon as a member of Galloanserae.
• Reexamination of specimens of Omorhamphus storchii and Gastornis parisiensis alleged to preserve alveoli for teeth is published by Louchart et al. (2021), who reject claims of presence of teeth in gastornithids.
• A study on the morphology of the dromornithid brain, based on data from dromornithid endocast material spanning from the late Oligocene to the late Miocene, is published by Handley & Worthy (2021).
• A study on the bone histology, growth dynamics and life history of Genyornis newtoni is published by Chinsamy & Worthy (2021).
• Redescription of Columba congi is published by Shen, Stidham & Li (2021).
• Oswald et al. (2021) recover a nearly complete mitochondrial genome of the Haitian cave rail (Nesotrochis steganinos) from fossils, and find this bird to be a relative of the families Sarothruridae and Aptornithidae rather than a rallid as previously thought.
• New fossil material of plotopterids, resembling bones of Olympidytes (which was previously considered endemic to North America), is described from the Eocene to Oligocene Itanoura and Kakinoura formations (Japan) by Mori & Miyata (2021), who interpret these fossils as indicating that early diversity of this family in Japan was higher than previously thought.
• A carpometacarpus of a petrel, potentially representing a new genus and species, is described from the Miocene Gaiman Formation (Argentina) by Piro & Acosta Hospitaleche (2021).
• A study on the anatomy and pneumaticity of the skull and on the paleoneurology of the fossil banded penguin Spheniscus urbinai is published by Acosta Hospitaleche, Paulina‐Carabajal & Yury‐Yáñez (2021).
• A study on the new referred material of Dryornis pampeanus from the Pliocene Chapadmalal Formation (Argentina) and on the phylogenetic relationships of this species is published by Degrange et al. (2021), who interpret D. pampeanus as the largest cathartiform reported to date.
• The first unequivocal fossil material of teratorns from the Pleistocene of South America is described from four fossiliferous localities of Central Argentina by Cenizo et al. (2021), who evaluate the implications of these fossils for the knowledge of the evolutionary history of teratorns, and update the taxonomy of the family.
• Redescription of the type specimen of Macrornis tanaupus from the Eocene Totland Bay Formation (Hampshire, United Kingdom) is published by Buffetaut & Angst (2021), who interpret this fossil as a partial tibiotarsus of a large terrestrial bird, possibly a phorusrhacid.
• A review of the knowledge of phorusrhacid skull anatomy is presented by Degrange (2021).
• Mayr, De Pietri & Scofield (2021) describe new fossil material of birds from the Eocene Nanjemoy Formation (Virginia, United States), including the first representatives of the families Messelasturidae, Psittacopedidae and Zygodactylidae from this formation.
• A distal end of the left tarsometatarsus of a phasianid, which represents the first avian fossil record of Taiwan, is described from the Pleistocene Chiting Formation (Tainan, Taiwan) by Tsai & Mayr (2021).

New taxa

Name	Novelty	Status	Authors	Age	Type locality	Country	Notes	Images
Apteryx littoralis	Sp. nov	Valid	Tennyson & Tomotani	Pleistocene		New Zealand	A kiwi.
Archaeodromus	Gen. et sp. nov	Valid	Mayr	Eocene (Ypresian)	London Clay	United Kingdom	A member of the family Archaeotrogonidae. The type species is A. anglicus.
Bitumenpicus	Gen. et sp. nov	In press	Campbell & Bocheński	Late Pleistocene	La Brea Tar Pits	United States (California)	A woodpecker. Genus includes new species B. minimus.
Breacopus	Gen. et sp. nov	In press	Campbell & Bocheński	Late Pleistocene	La Brea Tar Pits	United States (California)	A woodpecker. Genus includes new species B. garretti.
Bumbalavis	Gen. et sp. nov	Valid	Zelenkov	Late Paleocene-early Eocene	Naran-Bulak Formation	Mongolia	A member of the family Presbyornithidae. Genus includes new species B. anatoides.
Bumbanipes	Gen. et sp. nov	Valid	Zelenkov	Early Eocene		Mongolia	A member of Gruiformes showing the greatest similarity with modern limpkin. Genus includes new species B. aramoides.
Bumbanipodius	Gen. et sp. nov	Valid	Zelenkov	Early Eocene		Mongolia	A member of Galliformes showing morphological similarities with Argillipes aurorum and members of the family Quercymegapodiidae. Genus includes new species B. magnus.
Bumbaniralla	Gen. et sp. nov	Valid	Zelenkov	Early Eocene		Mongolia	Bird described on the basis of a coracoid, morphologically intermediate between those of Walbeckornis and members of the family Messelornithidae. Genus includes new species B. walbeckornithoides.
Bumbanortyx	Gen. et sp. nov	Valid	Zelenkov	Early Eocene		Mongolia	A small galliform bird showing morphological similarities with members of the families Quercymegapodiidae and Gallinuloididae. Genus includes new species B. transitoria.
Crosnoornis	Gen. et sp. nov	In press	Bocheński et al.	Oligocene (Rupelian)		Poland	A passerine, an early member of Suboscines. The type species is C. nargizia.
Eopelecanus	Gen. et sp. nov	Valid	El Adli et al.	Eocene (Priabonian)	Birket Qarun Formation	Egypt	A pelican. Genus includes new species E. aegyptiacus.
Fortipesavis	Gen. et sp. nov	Valid	Clark & O'Connor	Early Cretaceous (Albian)	Burmese amber	Myanmar	A member of Enantiornithes. The type species is F. prehendens.
Marambiornopsis	Gen. et sp. nov	Valid	Jadwiszczak, Reguero & Mörs	Eocene (Priabonian)	Submeseta Formation	Antarctica	A small-sized penguin. The type species is M. sobrali.
Melanerpes shawi	Sp. nov	In press	Campbell & Bocheński	Late Pleistocene	La Brea Tar Pits	United States (California)	A woodpecker, a species of Melanerpes.
Palaeogeranos	Gen. et sp. nov	In press	Louchart & Duhamel	Early Oligocene		France	A member of Gruoidea related to the limpkin and cranes. Genus includes new species P. tourmenti.
Parapsittacopes	Gen. et sp. nov	Valid	Mayr	Early Eocene	London Clay	United Kingdom	A relative of Psittacopes, Pumiliornis and Morsoravis. Genus includes new species P. bergdahli.
Pica praepica	Sp. nov	Valid	Boev	Early Pleistocene		Bulgaria	A species of Pica.
Procellaria altirostris	Sp. nov	Valid	Tennyson & Tomotani	Pliocene (Piacenzian)	Tangahoe Formation	New Zealand	A species of Procellaria.
Tynskya waltonensis	Sp. nov	Valid	Mayr	Eocene (Ypresian)	London Clay	United Kingdom	A species of the messelasturid Tynskya.
Ueekenkcoracias	Gen. et sp. nov		Degrange et al.	Eocene (Ypresian)	Huitrera Formation	Argentina	A member of the stem group of Coracii. The type species is U. tambussiae.

Pterosaurs

Research

• A study on the flight abilities of hatchling pterosaurs is published by Naish, Witton & Martin-Silverstone (2021).
• New information on the skeletal anatomy of Austriadraco dallavecchiai is provided by Dalla Vecchia (2021).
• An early juvenile or late hatchling specimen of Kunpengopterus sinensis, providing new information on the skeletal changes during ontogeny in wukongopterids, is described from the Tiaojishan Formation (China) by Jiang et al. (2021).
• Pêgas, Costa & Kellner (2021) attempt to reconstruct the adductor musculature of the pterodactyloid skull, and to estimate bite force for nine pterodactyloid species.
• Fragment of an ulna of a pteranodontid pterosaur is described from the Campanian locality Polunino 2 (Volgograd Oblast, Russia) by Averianov & Yarkov (2021), representing the first record of the family Pteranodontidae from the Lower Volga region reported so far.
• A review of putative boreopterid pterosaurs from the South Korea was published by Yun (2021), who concluded that they could not be confidently referred to Boreopteridae.
• New specimen of Istiodactylus latidens, probably coming from the Lower Cretaceous Vectis Formation (United Kingdom) and possibly representing the missing jaws of the holotype of this species, is described by Averianov et al. (2021).
• Bantim et al. (2021) describe a pteranodontoid pterosaur with anhanguerid affinities from Aptian-age deposits of the Romualdo Formation (Brazil).
• Solonin et al. (2021) describe teeth from the Upper Cretaceous (Santonian) Dmitrov Formation (Ryazan Oblast, Russia), referrable to ornithocheirid pterosaurs, leading to the first occurrence of them in said formation.
• Postcranial elements referrable to Lonchognathosaurus, confirming the validity of the genus and providing new information on the anatomy of this pterosaur, are described from the Lower Cretaceous Lianmuqin Formation (China) by Augustin et al. (2021).
• 114 small pterosaur footprints, possibly produced by pterosaurs belonging to the species Noripterus complicidens, are described from the Lower Cretaceous Shengjinkou Formation (China) by Li, Wang & Jiang (2021), who name a new ichnospecies Pteraichnus wuerhoensis.
• New fossil material of pterosaurs is described from the Lower Cretaceous Lianmuqin Formation (China) by Augustin et al. (2021), who interpret these fossils as probable evidence of the presence of a second dsungaripterid taxon (distinct from Lonchognathosaurus) in this formation.
• A study on the internal architecture and mechanical properties of a hyper-elongate cervical vertebra of an azhdarchid pterosaur from the Kem Kem Group (Morocco) is published by Williams et al. (2021).
• A large wing bone (possibly an ulna) of a pterosaur with an estimated wingspan comparable with the holotype specimen of Cryodrakon boreas is described from the Campanian Kaiparowits Formation (Utah, United States) by Farke (2021).

New taxa

Name	Novelty	Status	Authors	Age	Type locality	Country	Notes	Images
Javelinadactylus	Gen. et sp. nov	Valid	Nascimento-Campos et al.	Late Cretaceous (Maastrichtian)	Javelina Formation	United States (Texas)	A tapejarid. The type species is J. sagebieli
Kunpengopterus antipollicatus	Sp. nov	Valid	Zhou et al.	Late Jurassic (Oxfordian)	Tiaojishan Formation	China
Sinomacrops	Gen. et sp. nov	Valid	Wei et al.	Middle–Late Jurassic (Callovian–Oxfordian)	Tiaojishan Formation	China	An anurognathid. The type species is S. bondei.
Tacuadactylus	Gen. et sp. nov	Valid	Soto et al.	Late Jurassic (Kimmeridgian)	Tacuarembó Formation	Uruguay	A gnathosaurine ctenochasmatid. The type species is T. luciae

Other archosaurs

Research

• Marchetti et al. (2021) revise the tetrapod (including dinosauromorph) footprint assemblage from the Quarziti del Monte Serra Formation (Ladinian of Italy), and interpret this assemblage and other findings of Ladinian dinosauromorph footprints as evidence of wide dispersal of dinosauromorphs as early as the Middle Triassic.
• The first putative forelimb and pectoral girdle of Lagerpeton chanarensis is described by McCabe & Nesbitt (2021).
• A study on the nature of tooth attachment in silesaurids, and on its implications of the knowledge of the evolution of tooth attachment of archosaurs, is published by Mestriner et al. (2021).