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See detailA new titanosaur (Dinosauria: Sauropoda) from the Upper Cretaceous of Velaux-La-Bastide Neuve (southern France)
Díez Díaz, Verónica; Garcia, Géraldine; Pereda-Suberbiola, Xabier et al

in Historical Biology (2021)

Remains of Garrigatitan meridionalis nov. gen. et sp. were found in two bonebeds of sequence 2 from the upper Campanian site of Velaux-La Bastide Neuve (Aix-en-Provence Basin, Bouches du Rhône department ... [more ▼]

Remains of Garrigatitan meridionalis nov. gen. et sp. were found in two bonebeds of sequence 2 from the upper Campanian site of Velaux-La Bastide Neuve (Aix-en-Provence Basin, Bouches du Rhône department). The vertebrate assemblage is dominated by dinosaurs, including the titanosaur Atsinganosaurus velauciensis. Garrigatitan meridionalis presents three diagnostic characters: hourglass-shaped humeri (proximal and distal thirds of almost the same transversal width) in anterior and posterior views, ilium with a broad rounded hollow slightly posterior to the base of the pubic peduncle, proximolateral margin of the femur only slightly medially deflected. Garrigatitan was a small to medium-sized sauropod (sub/adult individuals between 4-6 metres and 2-2.5 tonnes), showing anatomical differences with Atsinganosaurus, and with the other Late Cretaceous Ibero-Armorican titanosaurs. Large titanosaurian specimens found at Velaux-La Bastide Neuve could belong to adult Garrigatitan individuals reaching a body length of at least 12 metres. Histological analysis of long bones shows features similar to other Late Cretaceous European titanosaurs, indicating that all individuals had reached skeletal maturity (presence of an EFS, heavy remodelling HOS 12 to 14). The new taxon is recovered within the clade Lirainosaurinae. Garrigatitan meridionalis increases the diversity of Late Cretaceous titanosaurs within the Ibero-Armorican Island. [less ▲]

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See detailWhen bone palaeopathologies play hide and seek: a case study on sauropod dinosaurs
Jentgen, Benjamin ULiege; Stein, Koen ULiege; Fischer, Valentin ULiege

Conference (2020, May)

Palaeopathology is the study of ancient pathologies preserved in the fossil record. While fossil pathologies have caught interests over the last decades, only those featuring externally-visible ... [more ▼]

Palaeopathology is the study of ancient pathologies preserved in the fossil record. While fossil pathologies have caught interests over the last decades, only those featuring externally-visible manifestations have been extensively studied. A study initially aimed at analysing growth dynamics of two basal sauropods (cf. Isanosaurus and Spinophorosaurus nigerensis) lead us to consider that several palaeopathologies have gone unnoticed. Indeed, our histological survey unexpectedly unveiled palaeopathologies that were not expressed externally, but well internally under the microscope. Both samples featured abnormal radial fibrolamellar bone that we interpret as spiculated periosteal reactions (‘hair-on-end’ and sunburst pattern for cf. Isanosaurus and S. nigerensis respectively). A neoplasmic origin for this bone tissue is favoured for the former specimen, whereas another neoplasmic origin or a viral condition are favoured for the latter. This indicates that several palaeopathologies have flown under the radar and that assessments of palaeopathological frequencies within fossilised populations likely underestimate the true value. We suggest that microscopic and/or CT scanning should become standard when assessing pathologies in the fossil record. [less ▲]

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See detailCase study of radial fibrolamellar bone tissues in the outer cortex of basal sauropods
Jentgen, Benjamin ULiege; Stein, Koen ULiege; Fischer, Valentin ULiege

in Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. (2020), 375(20190143), 1-12

The histology of sauropod long bones often appears uniform and conservative along their evolutionary tree. One of the main aspects of their bone histology isto exhibit a fibrolamellar complex in the ... [more ▼]

The histology of sauropod long bones often appears uniform and conservative along their evolutionary tree. One of the main aspects of their bone histology isto exhibit a fibrolamellar complex in the cortex of their long bones. Here, we report another bone tissue, the radial fibrolamellar bone (RFB), in the outercortex of the humeri of a young adult cf. Isanosaurus(Early to Late Jurassic,Thailand) and an adult Spinophorosaurus nigerensis (Early to Middle Jurassic, Niger) that do not exhibit any pathological feature on the bone surface. Its location within the cortex is unexpected, because RFB is a rapidly deposited bone tissue that would rather be expected early in the ontogeny. A palaeopathological survey was conducted for these sampled specimens. Observed RFB occurrences are regarded as spiculated periosteal reactive bone, which is an aggressive form of periosteal reaction. A ‘hair-on-end’ pattern of neoplasmic origin (resembling a Ewing’s sarcoma) is favoured for cf. Isanosaurus, while a sunburst pattern of viral or neoplasmic origin (resembling an avian osteopetrosis or haemangioma) is favoured for Spinophorosaurus. This study highlights the importance of bone histology in assessing the frequency and nature of palaeopathologies. [less ▲]

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See detailCases of pathological bone growth in Isanosaurus and Spinophorosaurus (Sauropoda): periosteal reaction and tumor-like conditions in dinosaurs
Jentgen, Benjamin ULiege; Stein, Koen ULiege; Fischer, Valentin ULiege

Conference (2019, July 03)

The long bone histology of sauropod dinosaurs appears uniform and conservative along the Sauropoda evolutionary tree. Fibrolamellar Complex (FLC), a scaffold of poorly and highly organized bone tissues ... [more ▼]

The long bone histology of sauropod dinosaurs appears uniform and conservative along the Sauropoda evolutionary tree. Fibrolamellar Complex (FLC), a scaffold of poorly and highly organized bone tissues, is the main 3D architecture building up the cortex of these bones. However, we report some Radial Fibrolamellar bone (RFB) in the outer cortex of the humeri of a young adult Isanosaurus (Nam Phong Formation, Upper Triassic of Thailand) and an adult Spinophorosaurus (‘Argiles de l’Irhazer’, Lower/Middle Jurassic of Niger). RFB is regarded as a fast-growing bone tissue and has been documented only in a few dinosaurian taxa including one titanosaur, but never among basal sauropods. Its outermost position within the cortex raises questions because such a rapidly apposited bone tissue would rather be expected in the inner cortex (corresponding to an early juvenile ontogenetic stage). Bone pathologies have been reviewed in order to determine whether these RFB occurrences are linked to a pathological condition. The RFB observed here is typical of periosteal reactions. Its ‘hair-on-end’ or sunburst appearance is probably related to sarcomas or metastasis around the coring sites than fracture/callus or bone infection, both of these last pathologies being completely absent from the sections and the sampled bone. Comparisons with human medicine studies and other periosteal reactions in dinosaurs are consistent with this interpretation. Intriguingly, the RFB of Spinophorosaurus is buried in the outer cortex, followed by a recovery of a ‘normal’ FLC. Spinophorosaurus thus survived its pathology and represents the first survival case of periosteal reaction-related event within Sauropoda. [less ▲]

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See detailComparative histology of dwarf titanosaurians from the Late Cretaceous of France
Jentgen, Benjamin ULiege; Stein, Koen ULiege; Díez Díaz, Verónica et al

Conference (2018, December)

The derived sauropod clade Titanosaurs encompasses the largest land animals that ever roamed the Earth as well as dwarfed species that evolved in restricted, insular habitats. Here, we report on the long ... [more ▼]

The derived sauropod clade Titanosaurs encompasses the largest land animals that ever roamed the Earth as well as dwarfed species that evolved in restricted, insular habitats. Here, we report on the long bone histology (humeri and femora) of several mature individuals belonging to a new, small-sized titanosaur from the Upper Cretaceous of Velaux – La Bastide Neuve (Provence, France). The main osteohistological feature of the new titanosaur is the heavy remodelling of the cortex, from the outermost cortex retaining some primary vascular canals with traces of External Fundamental System onsets (F to G bone tissue types) to the complete remodelling of the cortex (H bone tissue type). Histological Ontogenetic Stages (HOS) of the samples range from HOS 12 to 14, meaning these bones belong to mature close to or at final body size. Overall long bone histology of the new taxon is strikingly similar to that Atsinganosaurus velauciensis, another titanosaur from the same site and time period. A mature osteohistology combined with femora and humeri that are markedly reduced in size compared to more basal macronarians indicates an earlier onset of the remodelling process during ontogeny at a rate that surpassed the apposition one. Insular dwarfism is a consistent hypothesis for this combination of features, raising the number of dwarfed titanosaurs lineages in the European archipelago. [less ▲]

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See detailHet citizen-science project rond de Hobokense mammoet
Stein, Koen ULiege; Jentgen, Benjamin ULiege; Hellemond, Anthonie et al

in Belgische Vereniging voor Paleontologie & Werkgroep Pleistocene Zoogdieren (2018, November)

The Hoboken mammoth is a Belgian patrimonal piece of natural history that was mostly ignored since its discovery in 1865. The citizen-science program of the Flemish government was deemed ideal to study ... [more ▼]

The Hoboken mammoth is a Belgian patrimonal piece of natural history that was mostly ignored since its discovery in 1865. The citizen-science program of the Flemish government was deemed ideal to study the skeleton and provide a new reconstruction, find out its geological and individual age and get an insight into its state of preservation. Such a paleobiological study is crucial for a better understanding of the evolution of the Hoboken landscape and the Flemish Valley during the last 30.000 years. By actively involving citizen scientists (mostly volunteers, amateur paleontologists and schools) into the different steps of this multi-disciplinary investigation, the participants can obtain a thorough insight into the fundamental values of the STEM disciplines (science, technology, engineering and mathematics). The ultimate goal is to set-up a permanent exhibit in Hoboken with the reconstruction of the complete skeleton combined with the results of additional research on this unique Belgian mammoth. Unfortunately the project was not funded in the 2018 application round, but the authors continue searching for alternative funding. [less ▲]

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See detailCases of pathological bone growth in Isanosaurus and Spinophorosaurus (Sauropoda)
Jentgen, Benjamin ULiege; Stein, Koen ULiege; Fischer, Valentin ULiege

Poster (2018, July)

The histology of the long bone of sauropods appears uniform and conservative along the Sauropoda evolutionary tree. One of the main aspects of their bone histology is to exhibit a Fibrolamellar Complex ... [more ▼]

The histology of the long bone of sauropods appears uniform and conservative along the Sauropoda evolutionary tree. One of the main aspects of their bone histology is to exhibit a Fibrolamellar Complex (FLC) in the cortex of their long bones. However, we report Radial Fibrolamellar bone (RFB) in the outer cortex of the humeri of a young adult Isanosaurus (Histological Ontogenetic Stage – HOS – 8) and an adult Spinophorosaurus (HOS 12). RFB is regarded as a fast-growing bone tissue and has been documented in a few dinosaurian taxa, but never among Sauropoda. Its outermost position within the cortex raises questions, because such a rapidly apposited bone tissue would rather be expected in the inner cortex (corresponding to an early juvenile ontogenetic stage). Our thorough histological analysis of these specimens reveals some highly vascularized RFB yielding densely packed plump osteocyte lacunae that can even obscure the surrounding bone in both transverse and longitudinal sections. This osteocyte pattern is restricted to the RFB. Bone remodelling is more expressed in this cortical layer with more dense secondary osteons deposited in the RFB than more internally or externally. This contrasts with the other dinosaurian taxa affected by RFB which contains no secondary osteon in this bone tissue. The individual of Spinophorosaurus represents the first occurrence of RFB in Sauropoda buried in the outer cortex followed by a recovery of a ‘normal’ FLC after this event meaning this individual survived for some time after its phase of accelerated growth. This sequence of widely distinct modes of bone apposition suggests that these specimens are pathological. [less ▲]

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See detailA new titanosaurian sauropod from the Late Cretaceous of Velaux-La Bastide Neuve (Southern France)
Díez Díaz, Verónica; Garcia, Géraldine; Pereda Suberbiola, Xabier et al

Poster (2018, June)

The Upper Cretaceous site of Velaux-La Bastide Neuve (Bouches-du-Rhône Department, France) is well-known for its dinosaur specimens, more specifically the titanosaurian remains. The taxon Atsinganosaurus ... [more ▼]

The Upper Cretaceous site of Velaux-La Bastide Neuve (Bouches-du-Rhône Department, France) is well-known for its dinosaur specimens, more specifically the titanosaurian remains. The taxon Atsinganosaurus velauciensis is represented by several partially articulated skeletons found in this upper Campanian site; some of this material was described by Garcia and collaborators in 2010 based on teeth, elements of the axial skeleton, scapular girdle and limb bones. After a detailed revision of the fossil remains, including the study of new material collected during the 2009 and 2012 campaigns, the occurrence of a second titanosaurian species can be stated due to the morphological and histological dissimilarities present in the appendicular skeleton and the pelvic girdle. The long bone histology of the new taxon indicates slowly growing individuals near their growth end to fully grown individuals. Compared to the propodials of A. velauciensis which are fully grown, as indicated by their histology, but shorter than those of the new taxon, this osteological-histological combination points to bigger titanosaurian individuals. A phylogenetic analysis (in which all the Cretaceous European titanosaurs have been scored) recovers this new taxon in a polyphyletic group within Lithostrotia, together with the Iberoarmorican titanosaurs Lirainosaurus, Ampelosaurus and Atsinganosaurus, the African Rapetosaurus, and the Argentinean Bonatitan. Although its noticeable anatomical divergences with the rest of the European titanosaurs, this new taxon was probably closely related with other Iberoarmorican forms. New works on the European and African faunas will help to clarify these affinities. [less ▲]

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See detailLightning and the thunder: insular dwarfism inferred from long bone histology of the titanosaurian Atsinganosaurus velauciensis
Jentgen, Benjamin ULiege; Stein, Koen ULiege; Díez Díaz, Verónica et al

Poster (2018, June)

Titanosaurian sauropods include the largest land animals that ever walked on Earth. However, some of them evolved into dwarfed species, linked to their insular habitats. Here, we report on the long bone ... [more ▼]

Titanosaurian sauropods include the largest land animals that ever walked on Earth. However, some of them evolved into dwarfed species, linked to their insular habitats. Here, we report on the long bone histology of several mature individuals of the small-sized titanosaur Atsinganosaurus velauciensis from the Upper Cretaceous of Velaux – La Bastide Neuve (Provence, South-Eastern France). The completely remodelled H bone tissue type in all specimens characterizes mature and fully grown individuals. Together with the extensive bone remodelling, the samples range from HOS (Histological Ontogenetic Stages) 14 and from RS (Remodeling Stages) 13 to 14. Considering the reduced size of the sampled femur and humeri, the remodelling process would have begun early in the ontogeny of this titanosaur compared to non-titanosaurian sauropods, at a rate that surpassed the apposition rate. Thus, size reduction of A. velauciensis has to be taken into account to explain the advanced state of its long bone histology. Insular dwarfism is a consistent hypothesis for this combination of features and has been proposed for a series of other titanosaurs from the European archipelago (e.g. the Romanian Magyarosaurus dacus and the Spanish Lirainosaurus astibiae) that show comparable long bone histology and inferred body size. [less ▲]

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See detailThe titanosaurian dinosaur Atsinganosaurus velauciensis (Sauropoda) from the Upper Cretaceous of southern France: new material, phylogenetic affinities, and palaeobiogeographical implications
Díez Díaz, Verónica; Garcia, Géraldine; Pereda Suberbiola, Xavier et al

in Cretaceous Research (2018), 91

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See detailMegaloolithid dinosaur eggs: scrambled parataxonomy and nesting strategies
Jentgen, Benjamin ULiege; Fischer, Valentin ULiege; Stein, Koen ULiege

Poster (2017, June 02)

The detailed study of fossil dinosaur eggshells from Upper Cretaceous continental deposits from the Hateg Basin (Romania), the Arc Basin and Argentina and from the Thanetian of the Rians Basin (France ... [more ▼]

The detailed study of fossil dinosaur eggshells from Upper Cretaceous continental deposits from the Hateg Basin (Romania), the Arc Basin and Argentina and from the Thanetian of the Rians Basin (France) was made in order to test the robustness of fossil eggs' parataxonomy and to reveal novel data on dinosaur palaeobiology. µXRF, XRD and cathodoluminescence analyses attest a limited diagenesis on these fossils, which allow interpreting observed traits from a palaeobiological point of view. According to their microstructure, analysed eggs mainly belong to the titanosaur-related Megaloolithidae oofamily. Measured histological variables analysed through PCA - clustering unveil a weak megaloolithid parataxonomy scheme which needs to include whole shell units morphology forming the eggshell in addition to descriptions. XRD analyses point to an almost pure calcite eggshell composition (LMC) as well as a preferential orientation of this calcite along the shell unit growth axis, the latter involving biomechanical properties of the egg. Water vapour conductance (GH2O) estimation of some fossil eggshells together with the corresponding porosity - modelled mass pairs suggest that Hat eg and Arc Basins titanosaurs burrowed their nest in humid conditions. The vegetation-mount hypothesis is rejected whereas a hydrothermal environment is proposed for the Argentinian sample. [less ▲]

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