Max C Langer

• Dr.
• Professor (Associate) at University of São Paulo

Dinosaurs arose in the Late Triassic and diversified during the subsequent periods of the Mesozoic Era. The oldest unequivocal dinosaurs come from Carnian deposits of Brazil, Argentina, India, and Zimbabwe, with sauropodomorphs representing the bulk of this record. Saturnalia tupiniquim was described from Brazilian strata in 1999 as the first Carni...

No contexto do Projeto-Temático FAPESP No. 20/07997-4 "Explorando a diversidade dos dinossauros do Cretáceo Sul-Americano e suas faunas associadas", foram realizados nos anos de 2023 (03 a 17 de junho) e 2024 (23 de junho a 09 de julho) dois trabalhos de campo para os arredores de Bagua e Bagua Grande, Região do Amazonas, Peru. Os depósitos explora...

A fauna que habitou a região norte da América do Sul durante o Cretáceo ainda é relativamente pouco conhecida. Nas proximidades de Bagua (Região do Amazonas, Peru) afloram depósitos fossilíferos das formações Celendín (Cenomaniano-Campaniano) e Chota (Campaniano-Maastrichtiano), dos quais restos de invertebrados, vertebrados e plantas já foram repo...

Nos últimos anos, um número crescente de trabalhos tem documentado a presença de microestruturas identificadas como componentes celulares e de tecido mole em ossos de diferentes grupos de vertebrados fósseis, datando desde o Permiano. Entretanto, as particularidades diagenéticas sobre a preservação dessas microestruturas são pouco exploradas. Nesse...

Titanosaur sauropods are a common component of the Upper Cretaceous fauna of the Serra da Galga Formation, Triângulo Mineiro region, Minas Gerais, Brazil. Among these, three distinct tooth morphotypes are recognized and described here. One of the teeth represents the largest titanosaur tooth ever found, whereas others correspond to possible juvenil...

Com mais de 400 m², o Sítio Paleontológico de Cruzeiro do Oeste expõe rochas do Grupo Caiuá, Cretáceo da Bacia Bauru. Em um curto período entre 2014 e 2021, cinco novas espécies de tetrápodes foram descritas a partir de material extraído de área de cerca de 20m², de forma que muito resta ser explorado no sítio. Em 2015, o poder público municipa...

Com mais de 400 m², o Sítio Paleontológico de Cruzeiro do Oeste expõe rochas do Grupo Caiuá, Cretáceo da Bacia Bauru. Em um curto período entre 2014 e 2021, cinco novas espécies de tetrápodes foram descritas a partir de material extraído de área de cerca de 20m², de forma que muito resta ser explorado no sítio. Em 2015, o poder público municipa...

The Adamantina Formation is the most extensive and taxonomically rich unity within the Bauru Group (Upper Cretaceous). This unity is considered one of the complete fossil records of vertebrate continental communities during the Cretaceous Gondwanan landmasses. However, this important fossil record is mainly based on large and articulated remains, a...

The Bauru Basin bears one of the best sampled tetrapod paleofaunas of Brazil, with about 70% of this diversity collected from its deposits in São Paulo. Its fossils are known since the beginning of the 20th century, coming from all stratigraphic units of the Basin cropping-out in the state, i.e., Santo Anastácio, Araçatuba, Adamantina (alternativel...

A Bacia Bauru congrega um dos mais ricos conjuntos de somatofósseis de tetrá- podes do território brasileiro, sendo cerca de 70% dessa paleodiversidade procedente de seus depósitos em São Paulo. Com registros conhecidos desde o início do século XX, tais fósseis foram coletados em todas as unidades estratigrá cas da Bacia que a oram no estado, i.e.,...

The description of new titanosaur specimens unearthed from deposits of the Serra da Galga Formation (Bauru Group, Late Cretaceous) at the BR-262 site, near Peirópolis (Uberaba, Minas Gerais State, Brazil), sheds light on the taxonomy of two taxa previously known from the same area and geological unit: Baurutitan britoi and Trigonosaurus pricei. A c...

Osteoderms are mineralized structures embedded in the dermis, known for non‐avian archosaurs, squamates, xenarthrans and amphibians. Herein, we compared the osteoderm histology of Brazilian Notosuchia of Cretaceous age using three neosuchians for comparative purposes. Microanatomical analyses showed that most of them present a diploe structure simi...

Most crocodyliforms of the Bauru Group were found in rocks of the Adamantina Formation, whereas the younger Marília Formation is almost devoid of such fossils. Here, we provide a detailed comparative description of MPMA 02–0005/87, a large skull roof found in Marília Formation deposits of the Monte Alto area, assigning it to a new crocodyliform. De...

Turtles have a highly modified body plan, including a rigid shell that constrains postcranial anatomy. Skull morphology and neck mobility may therefore be key to ecological specialization in turtles. However, the ecological signal of turtle skull morphologies has not been rigorously evaluated, leaving uncertainties about the roles of ecological ada...

Abelisauridae is a diverse clade of theropod dinosaurs, geographically well-distributed especially in the southern continents during the Cretaceous. The record of abelisaurids in South America comes mainly from Patagonia, whereas in Brazil they are mostly represented by numerous dental crowns and isolated bones, with few formally named species, mos...

The early Mesozoic is marked by several global-scale environmental events, including the emplacement of large igneous provinces, such as the Siberian Traps, Wrangellia, and Central Atlantic Magmatic Province (CAMP). These have been hypothesised as drivers of the successful diversification of Pan-Aves, the lineage of archosaurs closer to birds than...

Carnian (Late Triassic) deposits of South America provide the oldest unequivocal dinosaur records worldwide, most of which has been assigned to the sauropodomorph lineage. This includes Eoraptor lunensis, Panphagia protos, and Chromogisaurus novasi, from the Ischigualasto Formation, Argentina, and Saturnalia tupiniquim, Pampadromaeus barberenai, Bu...

A new genus and species of Ephemeroptera, Astraeoptera cretacica gen. et sp. nov., is described from the Lower Cretaceous limestone of the Crato Formation (Brazil). The new taxon has the following diagnostic characters: veins MP2 e CuA straight at their bases, MA branching in the apical half of wing length, CuA not forked, cubital field with longit...

Here we present, for the first time, the use of finite element analysis to evaluate bites of two possible predators, a baurusuchid crocodyliform and an abelisaurid theropod into titanosaur osteoderms, in order to test if these structures could act as defensive tools. Our results showed that bites caused much less stress on osteoderms that did not w...

Lewisuchus admixtus is an early dinosauriform described by Alfred Romer in 1972 on the basis of a single, incomplete skeleton, collected in lower Upper Triassic rocks of the renowned Chañares Formation, at the Los Chañares type‐locality, La Rioja Province, north‐western Argentina. Recent field explorations to the type‐locality resulted in the disco...

Baurusuchidae is one of the most diverse notosuchian groups, represented by ten formally described species from the Upper Cretaceous deposits of the Bauru and Neuquén basins, respectively in Brazil and Argentina. Among these, recent phylogenetic analyses placed Wargosuchus australis, Campinasuchus dinizi, and Pissarrachampsa sera within Pissarracha...

Dinosaurs possess a form of tooth attachment wherein an unmineralized periodontal ligament suspends each tooth within a socket, similar to the condition in mammals and crocodylians. However, little information is known about tooth attachment and implantation in their close relatives, the silesaurids. We conducted a histological survey of several si...

The process of interpreting and evaluating a fossil is a difficult task. Isopoda is a species-rich group of peracarid eumalacostracans which represent quite a challenge when found as fossils, independent of whether we are working with fragmentary or more complete specimens. Here we describe a new fossil species of crustacean, Platuropodus odysseus...

Aeolosaurus is a late Cretaceous Titanosaur genus with two species discovered in Argentina and one in Brazil. Although the allocation of the Argentinean Aeolosaurus seems unequivocal, that is not the case for the Brazilian species Aeolosaurus maximus since several authors questioned its positioning into this genus, based on both anatomical and phyl...

Living archosaurs (birds and crocodylians) have disparate locomotor strategies that evolved since their divergence ∼250 mya. Little is known about the early evolution of the sensory structures that are coupled with these changes, mostly due to limited sampling of early fossils on key stem lineages. In particular, the morphology of the semicircular...

Sphagesauridae is a group of notosuchian crocodyliforms from the Late Cretaceous of South America characterized by highly specialized jaws and dentition. Here, we describe a new sphagesaurid from the Santo Anastácio Formation (Caiuá Group, Bauru Basin), south-east Brazil. The specimen is composed of a partial palate, neurocranium, mandible and frag...

Baurusuchidae is one of the most diverse groups of South American notosuchians, unambiguously recorded in Late Cretaceous deposits of Brazil and Argentina. The group is characterized by a reduced tooth formula, a lateromedially compressed rostrum, and a verticalized quadrate, representing one of the top predators of their faunas. Historically, skul...

Triassic beds from Argentina and Brazil provide the most relevant fossil record of early dinosauriforms in terms of numerical abundance and taxonomic diversity. This record currently represents the best source to understand the origin and early evolutionary radiation of dinosaurs. In the present paper we offer an updated review focused on the avail...

Pterosaurs were the first vertebrates to evolve powered flight¹ and comprised one of the main evolutionary radiations in terrestrial ecosystems of the Mesozoic era (approximately 252–66 million years ago), but their origin has remained an unresolved enigma in palaeontology since the nineteenth century2–4. These flying reptiles have been hypothesize...

Saturnalia tupiniquim foi o primeiro sauropodomorfo inequívoco reconhecido para os estratos Carnianos do Período Triássico. Portanto, os espécimes atribuídos a este táxon foram por vários anos a principal fonte de dados anatômicos a respeito deste grupo na alvorada da Era dos Dinossauros. Combinados, os três espécimes da série-tipo (Museu de Ciênci...

Caimaninae is one of the few crocodylian lineages that still has living representatives. Today, most of its six extant species are restricted to South and Central America. However, recent discoveries have revealed a more complex evolutionary history, with a fossil record richer than previously thought and a possible North American origin. Among the...

Present knowledge of Late Triassic tetrapod evolution, including the rise of dinosaurs, relies heavily on the fossil-rich continental deposits of South America, their precise depositional histories and correlations. We report on an extended succession of the Ischigualasto Formation exposed in the Hoyada del Cerro Las Lajas (La Rioja, Argentina), wh...

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Gruta do Ioiô is a cave part of Iraquara carstic system (Salitre Formation, Una Group). Located in the region of the Chapada Diamantina, northeastern Brazil, this partially submerged cave has yielded abundant fossil remains that until now included Siluriformes, an alligatorid crocodilian and a set of mammals, such as representatives of Mustelidae,...

Pleurodires are less diverse than cryptodires, together forming the two major lineages of crown turtles. Their fossil record, however, is rich. A particularly large number of fossil pleurodires, many belonging to the Podocnemidoidae, has been recovered from the Upper Cretaceous Bauru Group outcrops of south‐central Brazil. Herein we describe an add...

The diagnosis of Dinosauria and interrelationships of the earliest dinosaurs relies on careful documentation of the anatomy of their closest relatives. These close relatives, or dinosaur “precursors,” are typically only documented by a handful of fossils from across Pangea and nearly all specimens are typically missing important regions (e.g., fore...

The present 3D Dataset contains the 3D models of the skull, brain and inner ear endocast analyzed in "Gnathovorax cabreirai: a new early dinosaur and the origin and initial radiation of predatory dinosaurs". Model IDs Description M3#442 3D model of the skull M3#443 3D model of the braincase M3#444 Endocast of brain, inner ear, and cranial nerves Ta...

Predatory dinosaurs were an important ecological component of terrestrial Mesozoic ecosystems. Though theropod dinosaurs carried this role during the Jurassic and Cretaceous Periods (and probably the post-Carnian portion of the Triassic), it is difficult to depict the Carnian scenario, due to the scarcity of fossils. Until now, knowledge on the ear...

Saturnalia tupiniquim is a sauropodomorph dinosaur from the Late Triassic (Carnian–c. 233 Ma) Santa Maria Formation of Brazil. Due to its phylogenetic position and age, it is important for studies focusing on the early evolution of both dinosaurs and sauropodomorphs. The osteology of Saturnalia has been described in a series of papers, but its cran...

Chindesaurus bryansmalli is an early dinosaur of uncertain affinities from the Late Triassic Chinle Formation at Petrified Forest National Park, Arizona. Since its first description in 1995, the taxon has been considered a plateosaurid, a noneusaurischian saurischian, a herrerasaurid, and/or a non-neotheropod member of Theropoda. Chindesaurus bryan...

Noasaurines form an enigmatic group of small-bodied predatory theropod dinosaurs known from the Late Cretaceous of Gondwana. They are relatively rare, with notable records in Argentina and Madagascar, and possible remains reported for Brazil, India, and continental Africa. In south-central Brazil, the deposits of the Bauru Basin have yielded a rich...

We present a systematic revision of the ‘prosauropod’ dinosaur Unaysaurus tolentinoi. Past phylogenetic treatments of this taxon have presented it as a key constituent of the low-diversity Plateosauridae. This clade, along with Massospondylidae, is currently regarded as a relatively non-controversial example of monophyly within non-sauropodan sauro...

The stereospondylomorph temnospondyls form a diverse group of early tetrapods that survived the Permian–Triassic extinction event and radiated during the Triassic. They encompass Carboniferous and Permian taxa from central and eastern Europe, such as ‘archegosauroids’, and early-divergent Gondwanan forms, such as rhinesuchids. By the Early Triassic...

Uberabatitan ribeiroi is a Late Cretaceous titanosaur (Dinosauria, Sauropoda) from southeastern Brazil. Here we provide a detailed revision of all its available specimens, including new elements from the type-locality. One new autopomorphy is added to diagnosis of the taxon: astragalus with a well-developed anteroposterior crest that mediodistally...

The braincase anatomy of the sauropodomorph dinosaur Saturnalia tupiniquim from the Late Triassic (Carnian) Santa Maria Formation of Brazil is described for the first time using CT. The braincase is characterized by a semilunar depression on the lateral surface of the basisphenoid, an occipital condyle whose ventral margin lies dorsal to the ventra...

Sauropodomorphs are the most abundant and diverse clade of Triassic dinosaurs, but the taxonomy of their earliest (Carnian) representatives is still poorly understood. One such taxon is Pampadromaeus barberenai, represented by a nearly complete disarticulated skeleton recovered from the upper part of the Santa Maria Formation of Rio Grande do Sul,...

List of 413 characters employed in the phylogenetic analysis. (DOCX)

Character-taxon matrix. (DOCX)

Majority-rule consensus of the MPTs resulting from the phylogenetic analysis. (EMF)

The Late Triassic (Carnian) upper Santa Maria Formation of south Brazil has yielded some of the oldest unequivocal records of dinosaurs. Here, we describe a new saurischian dinosaur from this formation, Nhandumirim waldsangae, gen. et sp. nov., based on a semiarticulated skeleton, including trunk, sacral, and caudal vertebrae, one chevron, right il...

The origins of one of the most successful groups to roam the Earth, the dinosaurs, have been the subject of intense investigation. Dozens of new early members of the group have been discovered in recent years and novel, sometimes challenging, hypotheses attempt to explain the relationships among the major dinosaur lineages and their early offshoots...

Dinosaurs were ubiquitous in terrestrial ecosystems through most of the Mesozoic and are still diversely represented in the modern fauna in the form of birds. Recent efforts to better understand the origins of the group have resulted in the discovery of many new species of early dinosaur and their closest relatives (dinosauromorphs). In addition, r...

Here, we report a new material possibly referred to Armadillosuchus arrudai collected during 2013 in a locality situated 7 km south of Jales, São Paulo, from rocks of the Late Cretaceous, Adamantina Formation. Armadillosuchus arrudai is previously known from two specimens, collected from General Salgado, São Paulo, also from the Adamantina Formatio...

The rise of sauropodomorphs is still poorly understood due to the scarcity of well-preserved fossils in early Norian rocks. Here, we present an association of complete and exceptionally well-preserved dinosaur skeletons that helps fill that gap. They represent a new species, which is recovered as a member of a clade solely composed of Gondwanan Tri...

Sacisaurus agudoensis is the only silesaurid known from the Triassic beds of the Santa Maria Supersequence and the correlation of its type locality to the other Triassic deposits of south Brazil has always been controversial. In an attempt to improve this, a handful of dinosaur and cynodont remains found associated to S. agudoensis are here describ...

Metacryphaeus is a calmoniid trilobite genus from the Devonian Malvinokaffric Realm, exclusive to the Gondwanan regions. It includes eleven species, which are for the first time included here in a single phylogenetic analysis. The resulting hypotheses establish relations among the Metacryphaeus species with few ambiguities, also suggesting the incl...

Although Permian fossils have been known from the Parnaíba Basin for two centuries, and some faunal and flora elements are well known worldwide, research on the fossil assemblages from this basin has lagged relative to other, more accessible basins. In the last decade, however, there has been a significant increase in the study of fossils from the...

In the last three decades, records of tribosphenidan mammalsfrom India, continental Africa, Madagascar and South Americahave challenged the notion of a strictly Laurasian distributionof the group during the Cretaceous. Here, we describe a lowerpremolar from the Late Cretaceous Adamantina Formation, SãoPaulo State, Brazil. It differs from all known...

A new sauropodomorph dinosaur from the Late Triassic Candelária Sequence (Santa Maria Formation), south Brazil, Bagualosaurus agudoensis gen. et sp. nov., helps to fill a morphological gap between the previously known Carnian members of the group and younger sauropodomorphs. In some aspects, the skull, lower jaw, and dental anatomy of the new taxon...

An exceptional new specimen (CAPPA/UFSM 0035) of Buriolestes schultzi was discovered during recent fieldwork at the type locality of the taxon, which is Carnian in age (Late Triassic). This early sauropodomorph is peculiar owing to its faunivorous feeding habits, unusual amongst the members of this large omnivorous/herbivorous clade. The specimen i...

Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa–Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicaria...

The southern supercontinent of Gondwana was home to an extraordinary diversity of stem-crocodylians (Crocodyliformes) during the Late Cretaceous. The remarkable morphological disparity of notosuchian crocodyliforms indicates that this group filled a wide range of ecological roles more frequently occupied by other vertebrates. Among notosuchians, th...

Despite representing a key-taxon in dinosauromorph phylogeny, Lagerpertidae is one of the most obscure and enigmatic branches from the stem that leads to the dinosaurs. Recent new findings have greatly increased our knowledge about lagerpetids, but no phylogenetic analysis has so far included all known members of this group. Here, we present the mo...

The present 3D Dataset contains the 3D model analyzed in the following publication: Ferreira, G.S., F.V. Iori, G. Hermanson, and M.C. Langer 2018. New turtles from the Late Cretaceous of Monte Alto-SP, Brazil, including cranial osteology, neuroanatomy and phylogenetic position of a new taxon. PalZ. https://doi.org/10.1007/s12542-017-0397-x

Triassic dinosaurs from South Brazil are considered as some of the oldest known worldwide, but their precise correlation to other early dinosaur occurrences have proven difficult. The problem of such long-distance faunal correlations has been exacerbated by reliance on an equivocal tetrapod biostratigraphy and the lack of palynomorphs and other age...

A high diversity of land vertebrates is known from the Late Cretaceous deposits of the Bauru Basin, Brazil, including at least five turtle taxa, all belonging to the clade Podocnemidoidae. Some of the richest fossil sites of this basin are in the area of Monte Alto, which yielded several squamate, dinosaur, and crocodyliform taxa. Yet, the single t...

The evolutionary history of dinosaurs might date back to the fist stages of the Triassic (c. 250– 240 Ma), but the oldest unequivocal records of the group come from Late Triassic (Carnian – c. 230 Ma) rocks of South America. Here, we present the fist braincase endocast of a Carnian dinosaur, the sauropodomorph Saturnalia tupiniquim, and provide new...

The upper Triassic deposits of the Selous Basin in south Tanzania have not been prospected for fossil tetrapods since the middle of last century, when Gordon M. Stockley collected two rhynchosaur bone fragments from the so called ''Tunduru beds''. Here we present the results of a field trip conducted in July 2015 to the vicinities of Tunduru and Ms...

Supplementary Infomation and Figures