N E ev L Cetac w E Africa · 6Department of Geology, Faculty of Science, Assiut University, Assiut,...

Articleshttps://doi.org/10.1038/s41559-017-0455-5

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1Mansoura University Vertebrate Paleontology Center, Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt. 2Department of Biological Sciences, Ohio University, Athens, OH, USA. 3Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, OH, USA. 4Integrative Research Center, The Field Museum of Natural History, Chicago, IL, USA. 5Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA. 6Department of Geology, Faculty of Science, Assiut University, Assiut, Egypt. 7Department of Earth Sciences, Denver Museum of Nature and Science, Denver, CO, USA. 8Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA. 9Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA, USA. *e-mail: [email protected]

Numerous palaeobiogeographic studies have proposed hypotheses to explain the nature of the terrestrial ver-tebrate faunas that inhabited continental Africa dur-

ing the post-Cenomanian Cretaceous (PCC; ~94–66 million years ago)1–9. Some of these works have argued that the African mainland was home to an endemic terrestrial verte-brate assemblage that was isolated from other land areas on an ‘island continent’1–3,6, whereas others have postulated the exis-tence of Late Cretaceous dispersal routes between Africa and neighbouring landmasses that would have led to the devel-opment of faunal commonalities among these areas4,7,8,10. In particular, many studies have proposed the existence of biotic connections between northern Africa and southern Europe based largely on the presence of continental vertebrate taxa with hypothesized Gondwanan affinities in terminal Cretaceous deposits of the latter region4,8,10,11. Nevertheless, in the absence of anatomically and phylogenetically informative terrestrial ver-tebrate fossils from the PCC of continental Africa (including the then-conjoined Arabian Peninsula but excluding Madagascar) these hypotheses have remained essentially untestable.

Here we present a new titanosaurian sauropod dinosaur from the Late Cretaceous (Campanian) of Egypt that is represented by the most complete terrestrial vertebrate skeleton yet discovered from the PCC of the African mainland. Phylogenetic analysis of this com-paratively complete and informative taxon provides an opportunity

to test hypotheses of biotic connections between northern Africa and southern Europe during the PCC.

ResultsSystematic palaeontology.

Sauropoda Marsh, 1878Titanosauria Bonaparte and Coria, 1993

Lithostrotia Upchurch, Barrett and Dodson, 2004Mansourasaurus shahinae gen. et sp. nov.

Etymology. ‘Mansoura’, for Mansoura University in Mansoura, Egypt, home institution of the research collaborative that undertook the field and laboratory work; ‘sauros’, Greek, lizard. ‘shahinae’ honours M. Shahin for her contributions to the foun-dation of the Mansoura University Vertebrate Paleontology Center (MUVP).Holotype. MUVP 200, an associated partial skeleton consisting of cranial fragments, dentaries, cervical and dorsal vertebrae and asso-ciated ribs, scapulocoracoid, sternal plate, humeri, radius, metacar-pal III, metatarsals I, III and II or IV, probable partial osteoderms, and several unidentified fragments.Locality. North of the road between Mut and Balat, Dakhla Oasis, Western Desert of Egypt (Fig. 1a).Horizon. Upper member of the Upper Cretaceous (Campanian12–16) Quseir Formation.

New Egyptian sauropod reveals Late Cretaceous dinosaur dispersal between Europe and AfricaHesham M. Sallam 1*, Eric Gorscak 2,3,4, Patrick M. O’Connor 3,5, Iman A. El-Dawoudi1, Sanaa El-Sayed1, Sara Saber1,6, Mahmoud A. Kora1, Joseph J. W. Sertich7, Erik R. Seiffert8 and Matthew C. Lamanna 9

Prominent hypotheses advanced over the past two decades have sought to characterize the Late Cretaceous continental vertebrate palaeobiogeography of Gondwanan landmasses, but have proved difficult to test because terrestrial vertebrates from the final ~30 million years of the Mesozoic are extremely rare and fragmentary on continental Africa (including the then- conjoined Arabian Peninsula but excluding the island of Madagascar). Here we describe a new titanosaurian sauropod dinosaur, Mansourasaurus shahinae gen. et sp. nov., from the Upper Cretaceous (Campanian) Quseir Formation of the Dakhla Oasis of the Egyptian Western Desert. Represented by an associated partial skeleton that includes cranial elements, Mansourasaurus is the most completely preserved land-living vertebrate from the post-Cenomanian Cretaceous (~94–66 million years ago) of the African continent. Phylogenetic analyses demonstrate that Mansourasaurus is nested within a clade of penecontemporaneous titanosaurians from southern Europe and eastern Asia, thereby providing the first unambiguous evidence for a post-Cenomanian Cretaceous continental vertebrate clade that inhabited both Africa and Europe. The close relationship of Mansourasaurus to coeval Eurasian titanosaurians indicates that terrestrial vertebrate dispersal occurred between Eurasia and northern Africa after the tectonic separation of the latter from South America ~100 million years ago. These findings counter hypotheses that dinosaur faunas of the African mainland were completely isolated during the post-Cenomanian Cretaceous.

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Articles Nature ecology & evolutioN

Diagnosis. Mansourasaurus shahinae is regarded as a lithostrotian titanosaur on the basis of the following suite of synapomorphies: coracoid with squared anteroventral corner17,18; sternal plate length exceeds 70% that of humerus17,19; humeral distal condyles divided17,18; distal end of radius bevelled ~20 degrees relative to long axis17,18,20. Mansourasaurus is diagnosed by the following autapo-morphies: ten dentary tooth positions; dentary symphyseal region with pronounced ventral projection (‘chin’) that comprises about one-third of the dorsoventral depth of the anterior end of the bone; Meckelian groove faces predominantly ventrally; anterior to middle cervical centrum with foramen in posterior portion of lateral sur-face; anteroposterior length of parapophysis in anterior to middle cervical vertebra subequal to that of centrum; foramen in capi-tulotubercular web of anterior cervical rib; distal radius four times broader mediolaterally than anteroposteriorly.

DiscussionOsteological description. The skeleton of Mansourasaurus shahinae is the most complete terrestrial vertebrate specimen known from the PCC of the entire African continent (Fig. 1b,c). Although a few other African PCC sauropod fossils have been described, the majority con-sist of isolated, poorly informative bones21,22; the two exceptions in this regard are the holotypic scapula and forelimb of Angolatitan from the Turonian of Angola23 and a partial hind limb of an unidentified titanosauriform from the Maastrichtian of Morocco24. Consisting of parts of the cranial and postcranial skeletons, the Mansourasaurus specimen represents a titanosaurian individual estimated at 8–10 m in length (Fig. 1c; Table 1). Although the neurocentral sutures of the

vertebrae are fused, the scapula and coracoid are not, so we estimate that MUVP 200 was not skeletally mature at death.

Two cranium fragments and both dentaries are preserved (Fig. 2a–f). The left dentary is nearly complete, whereas the right preserves only the anterior end. The dentary curves medially, ren-dering the anterior part of the lower jaw parabolic in dorsal view (Fig. 2c), comparable to the condition in many other titanosauri-ans25–29 but unlike the squared snout of several South American titanosaurs30. The dentary of Mansourasaurus possesses ten alveoli, a uniquely low number within Titanosauria (the Ampelosaurus den-tary preserves nine alveoli but is slightly incomplete26). The symphy-seal region exhibits an unusually well-developed ‘chin’ (Fig. 2d–f). The symphysis is perpendicular to the long axis of the dentary, as in many other titanosaurians27–30. The Meckelian groove occupies the ventromedial surface of the dentary, opens mainly ventrally and persists for most of the length of the bone (Fig. 2e).

The three preserved cervical vertebrae are opisthocoelous, anteroposteriorly short and internally composed of camellate bone (Fig. 2g–i; see Supplementary Information). The neural arches and spines are tall relative to those of comparably positioned cervicals of most other titanosaurians. The lateral surface of the centrum is excavated by a fossa that occupies much of its length. In the anterior to middle cervical vertebra (Fig. 2h), the posterior region of the lat-eral surface exhibits a foramen anterior to the cotyle that is unique to Mansourasaurus among titanosaurians. In at least the two ante-rior-most cervicals, the parapophysis is more than half the length of the centrum, and in the anterior to middle cervical vertebra, it extends nearly the entire centrum length, an autapomorphy of

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Fig. 1 | Location, quarry map and skeletal reconstruction of Mansourasaurus shahinae gen. et sp. nov. (MuvP 200). a, A map of Egypt showing the location of the Dakhla Oasis, the type locality of Mansourasaurus (indicated by the dashed box). b, A site map showing the disposition of the skeletal elements in situ. c, A skeletal reconstruction in right lateral view, showing the preserved elements. The colour-coding in b and c is as follows: red, skull; purple, postcranial axial skeleton; blue, appendicular skeleton; green, osteoderm fragments.




ArticlesNature ecology & evolutioN

Mansourasaurus. The capitulotubercular web of the anterior cervi-cal rib is pierced by a foramen that represents another autapomorphy of Mansourasaurus (Fig. 2g). Two incomplete dorsal vertebrae are preserved (Fig. 2j,k). The more anterior dorsal vertebra consists of the centrum and the posterior centrodiapophyseal lamina (Fig. 2j),

whereas the other vertebra preserves the centrum and part of the neural arch (Fig. 2k). The opisthocoelous anterior dorsal centrum lacks a ventral keel and has a shallow, subcircular cotyle. The antero-posteriorly elongate lateral fossa (pleurocoel) is not subdivided by internal laminae. The other dorsal vertebra preserves the anterior and posterior centrodiapophyseal laminae and a weakly developed lamina dividing the centrodiapophyseal fossa.

The right scapulocoracoid is nearly complete (Fig. 2l). On the basis of their preservation, the dorsal margins of the coracoid and the acromial process of the scapula would have been flush, or at least at the same height. The depth of the acromial region is more than 275% that of the anterior scapular blade (Table 1), contrasting with the low acromion exhibited by some other titanosaurians31,32. The blade is D-shaped in cross-section with a medial concav-ity that is demarcated ventrally by a ridge that is also present in Ampelosaurus26 and Lirainosaurus32. Mansourasaurus also has a dorsomedial tubercle on the anterior scapular blade that occurs in Lirainosaurus32. The scapula contributes more to the glenoid than does the coracoid, unlike in Lirainosaurus (coracoid contributes more than scapula32) or Opisthocoelicaudia (subequal contribution31). The span of the coracoid is greater dorsoventrally than anteropos-teriorly, as in Ampelosaurus, but in Opisthocoelicaudia this condi-tion is reversed. The infraglenoid lip is not as well developed as in Opisthocoelicaudia31. The coracoid foramen is patent along the scapulocoracoid suture, as in a few other titanosaurs32,33. The right sternal plate (Fig. 2m) is crescentic and similar to those of other titanosaurians and closely related titanosauriforms17–19. Its length is roughly 76% that of the humerus, a ratio comparable to other lithostrotians17.

The proximolateral corner of the humerus (Fig. 2n) is squared, as in most titanosauriforms17. The deltopectoral crest is slightly mediolaterally expanded at its distal extreme, projects anteriorly and persists until approximately midshaft (Table 1). The ulnar and radial condyles are moderately developed anteroposteriorly and dis-tinct from one another. The anterior portion of the radial condyle is not divided, as in other titanosaurians17. The proximal end of the nearly complete left radius is mediolaterally expanded but damaged (Fig. 2o). The distal end is about four times wider mediolaterally than anteroposteriorly (Fig. 2p; Table 1); we consider this autapo-morphic of Mansourasaurus since most other titanosaurians do not exceed a ratio of approximately 2.0. The distal margin is distolater-ally bevelled at 20 degrees to the horizontal, as in saltasaurids17,18. The distal end of left metacarpal III is mediolaterally expanded and bevelled slightly distolaterally (Fig. 2q). Of the hind limb, only the right metatarsals I (Fig. 2r) and III (Fig. 2s) and a metatarsal II or IV (probably also right) are preserved. The mediolateral axis of the distal end of metatarsal I is bevelled. The proximal end of the stout metatarsal III is subovoid in outline, similar to that of Notocolossus34. Several flattened, elongate fragments with irregular outlines and interwoven bone texture probably represent pieces of osteoderms.

Phylogenetic and palaeobiogeographic analyses. We assessed the phylogenetic affinities of Mansourasaurus using the data set and analytical protocols presented in a previous study9 (see Methods and Supplementary Information). Mansourasaurus was recovered within a clade of penecontemporaneous (Campanian–Maastrichtian) saltasaurid titanosaurians that are otherwise known only from Europe and Asia (Fig. 3). Within this clade, Mansourasaurus is the sister taxon of the European Lohuecotitan, with a clade consisting of the European Lirainosaurus and the central Asian Nemegtosaurus and Opisthocoelicaudia as the sister taxon of Lohuecotitan + Mansourasaurus. A clade comprised of the European Ampelosaurus and Paludititan is the sister taxon of the clade containing all of these other Afro-Eurasian titanosaurs. Although clade posterior probabilities vary widely across the topology—probably due to missing data and the lack of overlap

Table 1 | Measurements (mm) of Mansourasaurus shahinae gen. et sp. nov. (MuvP 200)

DentaryAnteroposterior length (along straight line) 182L

Dorsoventral height, symphysis 40.8L, 36.0R

Dorsoventral height, ramus 24.9L, 29.0R

Anterior cervical vertebraAnteroposterior length, centrum (with condyle) 147

Dorsoventral height, centrum, posterior 69

Dorsoventral height, total 235

Middle to posterior cervical vertebraAnteroposterior length, centrum (with condyle) 200+

Dorsoventral height, centrum, posterior 127

Dorsoventral height, total 330

Anterior dorsal vertebraAnteroposterior length, centrum (with condyle) 148

Dorsoventral height, centrum, anterior 104

Transverse width, centrum, anterior 85

ScapulocoracoidR

Anteroposterior length, total 730

Dorsoventral height, scapula, glenoid–acromion 428

Dorsoventral height, scapula, anterior end of blade 128

Dorsoventral height, scapula, posterior end of blade 90

Anteroposterior length, coracoid 215

Dorsoventral height, coracoid 340

Sternal plateR

Anteroposterior length 470

Mediolateral width, anteroposterior midline 262

HumerusL

Proximodistal length 620

Proximodistal length, deltopectoral crest 275

Mediolateral width, midshaft 120

Mediolateral width, distal 75

RadiusL

Proximodistal length 380+



Anteroposterior breadth, distal 30

Metacarpal IIIL


Metatarsal IR



Metatarsal IIIR



+ : element incomplete, measurement as preserved; L: left; R: right.





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Fig. 2 | Skeletal anatomy of Mansourasaurus shahinae gen. et sp. nov. (MuvP 200). a, Skull fragment (frontal or parietal?) in ?dorsal view. b, Braincase fragment in ?posterior view. c, Dentaries in dorsal view. d–f, Left dentary in lateral (d), medial (e) and anterior (f) views. g, Anterior cervical vertebra in right lateral view. h, Anterior to middle cervical vertebra in right lateral view. i, Middle to posterior cervical vertebra in right lateral view. j, Anterior dorsal vertebra in ventral view. k, Dorsal vertebra (with superimposed dorsal rib) in left anterolateral view. l, Right scapulocoracoid in lateral view (with reconstructed dorsal margins of acromial region and coracoid indicated by dashed line). m, Right sternal plate in ventral view. n, Left humerus in anterior view. o,p, Left radius in anterior (o) and distal (p) views. q, Distal left metacarpal III in anterior view. r, Right metatarsal I in lateral view. s, Right metatarsal III in dorsal view. acp, acromial process; al, accessory lamina; al1, alveolus 1; al10, alveolus 10; bt?, basal tuber?; ca, coracoid articulation; cd, condyle; ch, ‘chin’ of dentary; cof, coracoid foramen; cor, coracoid; cpol, centropostzygapophyseal lamina; cprl, centroprezygapophyseal lamina; cr, cervical rib; ct, cotyle; dpc, deltopectoral crest; dr, dorsal rib; for, foramen; gl, glenoid; igl, infraglenoid lip; lf, lateral fossa (= pleurocoel); mg, Meckelian groove; ns, neural spine; pcdl, posterior centrodiapophyseal lamina; poz, postzygapophysis; pp, parapophysis; prdl, prezygodiapophyseal lamina; prz, prezygapophysis; rc, radial condyle; sc, scapula; scb, scapular blade; sct, supracoracoideus tuberosity; sprl, spinoprezygapophyseal lamina; uc, ulnar condyle; vp, ventral process.





of preserved skeletal elements of each taxon—the placement of Mansourasaurus with Eurasian titanosaurians is consistent across all phylogenetic models (see Supplementary Information). The Afro-Eurasian clade as a whole (that is, Ampelosaurus, Lirainosaurus, Lohuecotitan, Mansourasaurus, Nemegtosaurus, Opisthocoelicaudia and Paludititan) is supported by a unique combination of syn-apomorphies of the scapulocoracoid (scapular blade unexpanded,

scapular blade perpendicular to coracoid articulation, posterior margin of acromial process concave, coracoid foramen at margin of scapula–coracoid articulation). The Afro-Eurasian clade is, in turn, sister to a Pan-American clade comprised of the South American titanosaurs Baurutitan, Dreadnoughtus and Pellegrinisaurus and the North American Alamosaurus. The Afro-Eurasian and Pan-American clades are estimated to have diverged from one another

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Maxakalisaurus

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ParalititanNeuquensaurus

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Fig. 3 | Phylogenetic, temporal and palaeobiogeographic context of Mansourasaurus shahinae gen et sp. nov. and other saltasaurid titanosaurian sauropod dinosaurs. a, The palaeobiogeographical model proposed for a subset of post-Cenomanian saltasaurids. Note the division into Pan-American and Afro-Eurasian clades, proposed to have arisen as a consequence of the final tectonic separation of Africa and South America ~100 million years ago (Ma; see Supplementary Information). Palaeogeographic map © 2012 Colorado Plateau Geosystems Inc. (CPGI) of ref. 52 and reproduced with permission from CPGI. b, Results of the tip-dated Bayesian phylogenetic and BioGeoBEARS palaeobiogeographic analyses. The decimals represent the posterior probability for each node; estimated ancestral areas (colour-coded pie charts at nodes) denote the likeliest palaeogeographic range(s) at each node based on the DEC+ j and DIVALIKE+ j models; the light purple bars represent the 95% highest posterior density (HPD) for the timing of the divergence date at each node. The colour-coded bars for each terminal taxon indicate the palaeogeographic range and the 95% HPD of the recorded stratigraphic range of that taxon; the vertical line within each bar indicates the mean tip age within the 95% HPD of the stratigraphic range. The hatched area indicates the approximate timing of the final separation of Africa and South America. The geologic timescale is after ref. 53. A, Asia (magenta); E, Europe (teal); F, Africa (orange); N, North America (green); S, South America (red); U, Australia (lavender).





at approximately or shortly after the time South America and Africa separated (~100 million years ago35,36). Palaeobiogeographic analyses suggest that Mansourasaurus arrived in Africa via a dis-persal event from Europe during the latest Cretaceous (Fig. 3b; see Supplementary Information).

Implications for African PCC continental vertebrate faunas. The discovery of Mansourasaurus and the results of the analyses pre-sented herein hold significant palaeobiogeographic implications. Most importantly, the palaeobiogeographic affinities of terrestrial vertebrates that inhabited continental Africa during the PCC have historically been poorly characterized due to sparse sampling and a highly incomplete fossil record16,37,38. Although PCC terrestrial vertebrate fossils have previously been recovered from the African mainland and the then-contiguous Arabian Peninsula, almost all are fragmentary and not diagnostic to low taxonomic levels, and therefore have allowed for only coarse palaeobiogeographic infer-ences16,39–41. Despite this dearth of evidence, numerous authors have proposed hypotheses regarding the nature of African terrestrial vertebrate faunas during the PCC, ranging from assemblages domi-nated by relictual lineages that were geographically isolated on an ‘island continent’1–3 to those with close affinities to coeval taxa from southern Europe4,8,10,42. Until now, these scenarios had been based mostly on extremely limited and/or ambiguous evidence. Although the PCC non-marine vertebrate record of Europe is much more extensive than that of the African mainland, the European taxa that have previously been postulated as indicators of continental verte-brate dispersal between the two landmasses are problematic in this regard. Some (for example, the gar Atractosteus africanus, mawson-iid coelacanths and bothremydine turtles) were probably tolerant of salt water8,43,44, whereas others (for example, foxemydine turtles, the crocodyliform Doratodon and abelisaurid theropods) are of ambig-uous or even contradictory palaeobiogeographic affinities within Gondwana (for example, the hypothesized closest relatives of the French abelisaurid Arcovenator are from India and Madagascar45). Even European PCC titanosaurians, traditionally considered Gondwanan in origin10,42,46, have, until now, been of unclear phy-logenetic and palaeobiogeographic affinities8,47. Phylogenetic and palaeobiogeographic analyses of Mansourasaurus demonstrate its sister taxon relationship to the near-coeval European titanosaurian Lohuecotitan (as well as to other Eurasian forms, to the exclusion of taxa from elsewhere in Gondwana), thereby offering the most robust support to date for non-marine vertebrate dispersal between Africa and Europe during the late Mesozoic. The new Egyptian titanosaur therefore emphasizes the need for fossils that are diag-nostic and phylogenetically informative at low taxonomic levels to enable the adequate assessment of palaeobiogeographic hypotheses.

MethodsPhylogenetic and palaeobiogeographic analyses. We used the data set and analytical protocols presented in a previous study9 (see Supplementary Information) to investigate the phylogenetic and palaeobiogeographic affinities of Mansourasaurus. The data set consists of 52 taxa and 503 morphological characters (including autapomorphies), making it one of the most comprehensive phylogenetic data sets yet assembled for titanosaurian sauropods. We analysed the data using recently developed Bayesian tip-dating phylogenetic methods and model-based palaeobiogeographic analyses9,48–50. Stratigraphic ranges for each taxon were obtained from the technical literature (see Supplementary Information) and sampled under a uniform prior distribution. Characters were assumed to be unordered and rates of character evolution were variable with rates drawn from a gamma distribution. We used the birth–death skyline serial-sampling tree model51—which assumes that birth and death rates may vary through time—and a lognormal relaxed clock model. The model ran for 20 million generations with sampling occurring every 1,000 generations followed by a 25% burn-in to discard the initial climbing phase. An alternative model was tested with similar assumptions except characters evolving under equal rates; however, the variable rates model was strongly favoured over the equal rates model and used for the palaeobiogeographic analysis. BioGeoBEARS was used for the palaeobiogeographic analysis and tested three models (DEC, DIVALIKE and BAYAREALIKE) with

alternative models with the additional + j parameter to facilitate long-distance dispersal events alongside the assumptions of each model49.

Life Science Reporting Summary. Further information on experimental design is available in the Life Sciences Reporting Summary.

Data availability. Data have been deposited in ZooBank under Life Science Identifier urn:lsid:zoobank.org:act:81FD8987-8020-4C57-AABF-13DE9A9BB819. The authors declare that all other data supporting the findings of this study are available within the paper and its Supplementary Information.

Received: 26 June 2017; Accepted: 15 December 2017; Published: xx xx xxxx

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AcknowledgementsWe thank A. Othman and A. Habib of the Faculty of Science at Mansoura University for logistical support, and M. El-Amir and F. Ibrahim (MUVP) for their critical roles in the field and laboratory work. A. McAfee skilfully executed the skeletal reconstruction in Fig. 1c and contributed greatly to Fig. 2, the other components of Fig. 1, and Supplementary Figs. 1–18. D. and R. Blakey kindly provided permission to reproduce the palaeogeographic map in Fig. 3a. We thank M. D’Emic and V. Díez Díaz for discussions, and V. Díez Díaz for providing unpublished photographs of the dentary of Ampelosaurus. Funding was provided by grants from Mansoura University, the Jurassic Foundation, the Leakey Foundation, the National Geographic Society/Waitt Foundation (grant no. W88-10) and the National Science Foundation (EAR-1349825 to P.M.O.).

Author contributionsH.M.S. directed the project and supervised the collection of the fossils in the field; H.M.S., I.A.E-D., S.E-S., S.S. and M.A.K. collected the fossils; I.A.E-D. and S.E-S. supervised fossil preparation; I.A.E-D. curated and measured the fossils; fossils were described by E.G., P.M.O., I.A.E-D. and M.C.L.; phylogenetic analysis was performed by E.G.; H.M.S., E.G., P.M.O., I.A.E-D., J.J.W.S., E.R.S. and M.C.L. wrote the paper.

Competing interestsThe authors declare no competing financial interests.

Additional informationSupplementary information is available for this paper at https://doi.org/10.1038/s41559-017-0455-5.

Reprints and permissions information is available at www.nature.com/reprints.

Correspondence and requests for materials should be addressed to H.M.S.

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.


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http://scienceviews.com/photo/library/SIA3584.html

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https://doi.org/10.1038/s41559-017-0455-5

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nature research | life sciences reporting summ

aryJune 2017

Corresponding author(s): Hesham M. Sallam

Initial submission Revised version Final submission

Life Sciences Reporting SummaryNature Research wishes to improve the reproducibility of the work that we publish. This form is intended for publication with all accepted life science papers and provides structure for consistency and transparency in reporting. Every life science submission will use this form; some list items might not apply to an individual manuscript, but all fields must be completed for clarity.

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Experimental design1. Sample size

Describe how sample size was determined. The new titanosaurian sauropod dinosaur taxon described in this study is represented by a single partial skeleton, MUVP 200. A sauropod ulna (MUVP 201) was recovered ~20 m from MUVP 200 and is described in the online supplement.

2. Data exclusions

Describe any data exclusions. No relevant data were excluded from the analysis.

3. Replication

Describe whether the experimental findings were reliably reproduced.

No experiments (in the strict sense of the word) were performed; hence, this field does not apply to our study.

4. Randomization

Describe how samples/organisms/participants were allocated into experimental groups.

There were no experimental groups; hence, this field does not apply.

5. Blinding

Describe whether the investigators were blinded to group allocation during data collection and/or analysis.

There was no group allocation; hence, this field does not apply.

Note: all studies involving animals and/or human research participants must disclose whether blinding and randomization were used.

6. Statistical parameters For all figures and tables that use statistical methods, confirm that the following items are present in relevant figure legends (or in the Methods section if additional space is needed).

n/a Confirmed

The exact sample size (n) for each experimental group/condition, given as a discrete number and unit of measurement (animals, litters, cultures, etc.)

A description of how samples were collected, noting whether measurements were taken from distinct samples or whether the same sample was measured repeatedly

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SoftwarePolicy information about availability of computer code

7. Software

Describe the software used to analyze the data in this study.

The phylogenetic and palaeobiogeographic methods used in our study are extensively described in the Methods section of our main text and in our online supplement. Parsimony analyses were conducted using PAUP v4.0a157. Tip-dating Bayesian phylogenetic analyses were conducted using BEAST v2.4.4. The R package BEASTmasteR was used to construct all XML files. The BEASTlabs, BDSKY, SA, phylodynamics, and CA packages were installed into BEAUTi v2.4.4 so that the tip-dating analyses would operate properly. Convergence, effective sample size (greater than 200) of pertinent parameters, and model likelihood scores were calculated in Tracer v1.6. The R package BioGeoBEARS was used to conduct palaeobiogeographic analyses on the variable rates tip-dated Bayesian topologies.

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Indicate whether there are restrictions on availability of unique materials or if these materials are only available for distribution by a for-profit company.

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Describe the antibodies used and how they were validated for use in the system under study (i.e. assay and species).

No antibodies were used.

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No eukaryotic cell lines were used.

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