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ORYCTOS,Vol. 1 : 105-112,Octobre 1998

A NE\ryDROMAEOSAURID THEROPOD FROMTHE UPPERCRETACEOUS OF SOUTHERNFRANCE.

Jean LE LOEUFF'and Eric BUFFETAUT'

'Muséedes Dinosaures, 11260 Espéraza, France. 2CentreNational de la RechercheScientifique, Cour du Liégat,75013 Paris, France.

Abstract : New dromaeosauridremains from the Upper Cretaceousof southern France (Var Department, Fox- Amphoux syncline) include vertebraeand a right humerus.This material belongs to a new and speciesof dro- maeosaurid,described as Variraptor mechinorun. Among its derived featuresare double pleurocoels on the cervi- co-dorsal vertebraeand a strong medial tubercle on the humerus. Variraptor mechinorum is interpreted as a repre- sentativeof an isolated European lineage of dromaeosauridswhich evolved from an Early CretaceousEuramerican ancestralstock.

Key words : ,, Varirapto4 Late ,France

[Jn nouveau Théropode dromaeosauridé du Crétacé supérieur du Sud de la France

Résumé : Des nouveauxrestes de Dromaeosauridaedu Crétacésupérieur du Sud de la France sont décrits. Ce maté- riel est rapporté à un nouveau geme et une nouvelle espèce,Variraptor mechinorum. défini par plusieurs caractères dérivés comme la présencede doubles pleurocoeles sur les vertèbres cervico-dorsaleset d'un puissant tubercule médial sur I'humérus. Vartraptor mechinorum est interprété comme le représentantd'une lignée européennede Dromaeosauridae ayant connu une évolution endémique à par$r de formes euraméricaines du Crêtacé inférieur.

Mots clés : Theropoda,Dromaeosauridae, Uariraptor Crétacé supérieur;France

INTRODUCTION systematic excavations near Fox-Amphoux were conducted by Lapparent in 1939 (Lapparent 1947) at The new dromaeosauridremains described here were the farm of Métisson. Further excavations were discoveredby Patrick and Annie Méchin at the undertaken at Métisson in the late 1970s by a team BastideNeuve locality, in the Fox-Amphouxsyncli- from the Museum National d'Histoire Naturelle of ne, 35 km west of Draguignan (Var Department, Paris and the University of Paris (Broin et al. 1980). France, figure 1). The locality exposessediments The new Bastide Neuve locality has yielded a rich belongingto the Grèsà ReptilesFormation, which is vertebrate fauna comprising chelonians Late or Early in age (Podocnemididae), crocodiles (Alligatorid àe, (Westphal8. Durand 1990; Buffetaut &. Le Loeuff Crocodylidae), (Dromaeosaurid4e, I99I). The Fox-Amphoux syncline localities were Titanosauridàe, Ornithopoda, Ankylosauria) and discoveredduring the first half of the nineteenthcen- (cf. Buffetaut et al. 1995). tury and were mentioned by Doublier (1842), Museum repositories are indicated as follows : Panescorse(1871) and Matheron(1891). The first MDE = Musée des Dinosaures,Espéraza, France.

105 ORYCTOS,Vol. 1, 1998

A Montmeyan

SYSTEMATIC PALAEONTOLO GY

SubclassDIAPSIDA Osborn,1903 Fox-Irmphoux

MegaorderDINOSAURIA Owen, 1842

OrderTHEROPODA Marsh, 1881

InfraorderMANIRAPTORA Gauthier,1986

Family DROMAEOSAURIDAE Matthew et Browil, 1922 FIG. 1 : Location map; Bastide Neuve is indicatedby the star; scalebar : 2.5 km.

GenusVARIRAPTOR gen. nov. Referred material. A right humerus (MDE-D158), a cervico-dorsal ver- ïYpe . tebra (Méchin Collection; cast MDE-DOI), a sacro- Variraptormechinorltm sp. nov. caudal vertebra (Méchin Collection), and a femur (Méchin Collection; cast MDE -D49). Le Loeuff et al. Derivation of name. (1992) referred the cervico-dorsal (fig. 6) and the From the French Var (a river and an administrative sacro-caudaldiscovered at Roques-Hautes(Bouches- department)and the Latin raptor (thief). du-Rhône Department, Grès à Reptiles Formation, Campanian-Maastrichtian) to an undetermined dro- Diagnosis. maeosaurid. Sacral five from Bastide Neuve (see As for the and only species. below) has exactly the same shapeas the sacrocaudal from Roques-Hautes (cf. Le Loeuff et al. 1992, p. Variraptormechinorum sp. nov. 34I : fig. 2), and it is likely that both belong to the figures2-6 same species.Therefore, the Roques-Hautesmaterial is used to augment the diagnosis of the French mani- Derivation of name. raptoran described here. After Patrick and Annie Méchin, who collectedthe material and kindly presentedthe to the Diagnosis. The cervico-dorsal vertebrae have a pro- Muséedes Dinosaures, Espéraza. minent epipophysis and very developedhypapophysis; the cervico-dorsals bear two pleurocoels; the cervico- Holotype. dorsals to the last dorsal bear a hyposphen-hypantrum An articulatedposterior dorsal vertebra (MDE-D 168) articulation; the centra shorten from the anterior to the and (MDE-D169). posterior dorsals; the sacrum consists of five coossi- fied sacral vertebrae; the sacrocaudal vertebra has a TVpehorizon and locality. trapezoidal centrum; the transverse processesof the Grès à ReptilesFormation; Late Campanianto Early sacrocaudal are aliform; the humerus has a well-deve- Maastrichtian (Buffetaut &. Le Loeuff l99I); La loped deltopectoral crest and internal tubercle and also BastideNeuve (Fox-Amphoux,Var, France). bears a strongly developed medial tubercle.

106 LE LGUFF & BUFFETAUT- NEV/DROMAEOSAURID

FIG. 2 : Variraptormechinorum gen et sp.nov., MDE-D 168,Bastide Neuve (Var department,France,Maastrichtian) : last dorsalvertebra in cranial(A), lateral(B) and caudal(C) views; scalebar represents20 mm.

DESCRIPTION

The new material from Fox-Amphoux consists of a last dorsal vertebra which was found articulated with a complete sacrum and an isolated humerus. The posterior dorsal (MDE-D168; fig. 2) lacks Ir both prezygapophyses,the left postzygapophysis and the extremities of the neural spine and diapophyses. In additior, the parapophyses are broken. The short centrum is amphicoelous and bears a small pleuro- coel. The preserved postzygapophysial facet is concave, the medial part (hyposphene) vertical, and the external face subhorizontal. The neural spine is short cranio-caudally with prominent qanial and caudal ridges representing attachment scars for the interspinous ligament. In lateral view, â deep fossa is limited by the infradiapophysial laminae and the parapophyses.An upper fossa is present above the horizontal lamina between the diapophysis and the prezygapophysis.

FIG. 3 : Variraptor mechinorum gen et sp. nov., MDE-DI69, Bastide Neuve (Var department, France,Maastrichtian): sacrum in dorsal (A), left lateral (B), ventral (C) and right lateral (D) views ; scalebtff represents20 mm. r07 ORYCTOS,Vol. 1, 1998

FIG.4 : Variraptormechinorum gen. et sp.nov., MDE-D169, Bastide Neuve (Var department,France,Maastrichtian): sacrum in caudal(A) andcranial (B) views;scale bar represents 10 mm.

The sacrum (MDE-DI69; figs 3-4) is 160 mm respectively. The transverse processes are directed long and composed of five fused vertebrae.In ventral laterally, caudally and slightly upward. Sacral five view the junctions between the centra are marked by has wide aliform transverse processes originating conspicuous ridges. The first centrum is the shortest from the middle of the centrum and oriented in the (25 mm) and the deepest (anterior height: 25 mm). same direction as the preceedingprocesses. The neu- Sacral two is 27 mm long, while sacrals three and ral spines of sacrals one to three are partially preser- four aîe 32 Tnm and sacral five is 30 mm long. The ved: they are completely coossified and form a thin, ventral face of the first centrum is concave from front blade-like structure. to back and transversely rounded, with two deep and The humerus (MDE-D158; fig. 5) is I95 mm thin fossae. Small foramina open at the bottom of long. Although somewhat crushed, it is almost com- these fossae.The succeedingcentra also show a cra- plete except for the thin deltopectoral crest which niocaudal concavity in lateral view. Centra two to lacks its proximal tip. The delto-pectoral crest four are transversely shorter than centrum one. At the expands for about 70 mm below the head and lateral- junction between sacral three and four there is a deep ly meets a prominent ridge which separated the longitudinal ventral groove. Sacral five is caudal-like insertion areaof the M. brachialis from that of the M. and its box-like centrum bears a shallow ventral groo- humero-radialis (Ostrom 1969). This conspicuous ve. protuberance is the most remarkable character of the In cranial view sacral one retains the appearance bone and is more developed than in any other thero- of a dorsal vertebra, with a slightly concave articular pod, including .As suggestedby Ostrom face of the centrum. A foramen opens below the pre- (1969), it 'would indicate that these muscles were zygapophyses, the facets of which are oblique. In unusually large' and suggestsa raptorial function for caudal view, the centrum of sacral five has a slightly the forearm. The internal tubercle is also very deve- concave trapezoidal articular face. Aliform traqsverse loped (comparable again to Deinonychus), projecting processes arise from the junction between the cen- backward from the medial caudal surface of the head, trum and neural arch. whereas in Deinonychus it forms only a short rugose In lateral view sacral one though damaged clear- crest. At the distal end of the humerus, the radial ly retains a large pleurocoel. Sacral two also bears a condyle was larger than the, now broken, ulnar small pleurocoel in a deep fossa while sacral three condyle. The size of the humerus indicates an retains only a slight lateral excavation. No pneum atic slightly smaller than Deinonychus. foramen is visible on the Iaterul faces of sacrals four and five. The transverse processes of sacral one were COMPARISONS situated near the cranial end of the vertebra and aîe not preserved. In sacrals two, three and four, the Various lines of evidence suggest that the thero- transverse processes overlap the junctions between pod material from the Grès à Reptiles Formation repre- sacrals one and two, two and three, and three and four sents a dromaeosaurid.The presence of a prominent

108 LE LGUFF & BUFFETAUT - NEW DROMAEOSAURID

F'IG.5 : Variraptor mechinlrum gen.et sp. nov, MDE-D 158, BastideNeuve (Var department, France,Maastrichtian): right humerus in caudal(A), lateral(B),, cranial (C) and medial(D) views;scale bar represents20 mm.

epipophysis and a well-developed hypapophysis on may (according to its origin) belong to this taxon. As the cervico-dorsals are synapomorphies of the far as we know, troodontid sacra, which have six (Gauthier 1986). Within this group, it fused vertebrae (Currie 8. Russell 1988; Howse & seems that only the Dromaeosauridae retained five Milner 1993; Russell & Dong 1993) are significantly sacral vertebtae, although there is some uncertainty different from the sacrum of . in this regard. Ostrom (I97 6) briefly described the Oviraptorids, elmisaurids and ornithomimosaurs sacrum of Deinonychus antirrhopus as having five have more than five sacral vertebrae (Holtz 1994). coossified vertebtae,but also noted that "a sixth cen- Other dromaeosaurid characters of the French trum, presumably representing the last dorsal, seems material include : the sacrocaudalshave the same tra- to be fused to the first sacral". ITIthis case,the sacrum pezoidal centrum as the anterior caudals of of V mechinorum would appearto be more conserva- Deinonychus antirrhopus (cf. Ostrom 1969) and the tive when compared with that of Deinonychus. last dorsal'from Bastide Neuve with its hyposphene- However, Ostrom (1990) mentioned the occulrence hypantrum articulation is also reminiscent of the pos- of only three or four sacral vertebrae in dromaeosau- terior dorsals of Deinonychus, . The humerus from rids. In the dromaeosaurid Saurornitholestes, there Bastide Neuve, with its well-developed deltopectoral are five sacral vertebrae (Makovicky 1995). Howse crest and medial tubercle, is also reminiscent of that and Milner (1993) described a sacrum from the Late of Deinonychus but the medial tubercle is much Cretaceous of Canada as a troodontid sacrum. This stronger. From these comparisons, it appearsthat the sacrum comprises five vertebrae and probably maniraptoran material from Southern France belongs belongs to a dromaeosaurid,because the last vertebra to a dromaeosaurid.Further comparisons with descri- has distinctive aliform processes, and a trapezoidal bed dromaeosaurids necessitatea review of the avai- caudal articulation of the centrum. H. D. Sues (pers. lable data,given in a chronological , from oldest comm.) notes that this centrum is almost identical to to youngest. the undescribed sacrum of Saurornitholestes and

109 ORYCTOS,Vol. 1, 1998

FIG" 6 : Variraptor mechino rum gen. et sp.nov., Roques-Hautes, ?Maastrichtian: cervico-dorsalvertebra (CastMDE-D0l ) in cranial (A).,lateral (B), caudal(C), ventral(D) and dorsal(E) views;scale bar representsl0 mm.

Deinonychus antirrhopus Ostroffi, 1969 has been albertensis Matthew and described from the Cloverly Formation of Wyoming, Brown, 1922 from the Judith River Formation is Montanî, USA (Aptian-Albian). Significant resem- known from apartial skull and foot elements and thus blances to Variraptor include the .epipophysis and cannot be compared with the French form. The same hypapophysis of the cervico-dorsal, five coossified is true for Hulsanpes perlei Osmolska, 1982 known sacrals,the trapezoidal sacrocaudalcentrum, and the from a partial foot from the well-developed deltopectoral crest and internal of (Campanian), and mongo- tubercle of the humerus. The main differences arethe liensis Barsbold, 1983 , of which afragmentary skull, two pleurocoels of the cervico-dorsal, and the very a pelvis and manus and foot elements have been des- strongly developed medial tubercle of the humerus. cribed from the of Mongolia Saurornitholesteslangstoni Sues, 1978 from the (Campanian or Maastrichtian). Judith River Formation (Campanian) of Alberta, Elopteryx nopcsai Andrews, I9I3, from tlie Late Canada, is known from well-preservedskeletons, but Maastrichtian of Romania may be a dromaeosaurid only the skull material has been published so far . (cf. Le Loeuff et al. 1992), but it is known only from Vertebral material has been described in Makovicky's a femur and metatarsals. unpublishedthesis (1995). From thesecomparisons, it seemspossible to dif- mongoliensis Osborn, 1924 ferentiate the French dromaeosaurid from (, Mongolia, Campanian) is not Deinonychus antirrhopus, and consider it as a new adequately described and cannot be compared with genus and species,Variraptor mechinorum. The phy- the French dromaeosaurid. logenetic relationships of dromaeosaurid taxa are still

110 LE LGUFF & BUFFETAUT- NEW DROMAEOSAURID poorly understood, owing largely to the fact that Drawingswere madeby Guy Le Roux at the Musée many of them are incompletely described, hence the des Dinosaures,Espétaza. This work was supported position of Variraptor mechinorum among dromaeo- by the Association Dinosauria (Musée des saurids is uncertain. Dinosaures,Espéraza) and the Institut National des Sciencesde I'Univers. CONCLUSIONS REFERENCES From a palaeobiogeographicalpoint of view, the ANDREWS, C. W. 1913. On some remains from the Upper Cretaceousof Transylvania.Geological Magazine, 5 : 193-196. presence of dromaeosaurid theropods in Europe at BARSBOLD, R. 1983. [Carnivorousdinosaurs from the Cretaceous the end of the Cretaceousis not unexpected.They can of Mongolial. Transactions of the joint Soviet-Mongolian be considered as vestigial taxa from an Early PaleontologicalExpeditions,19 : I-In. [In Russian]. Cretaceous Euramerican palaeobioprovince, which BROIN, F. de; BUFFETAUT, E.; CAPPETTA, H.; KEROURIO, P.; broke up during the Aptian following transgression KOENIGUER, J. C.; RUSSELL, D.; SECRETAN, S.; SIGO- by epicontinental seas. Early Cretaceous dromaeo- GNEAU-RUSSELL, D.; TAQUET, P. & WENZ, S. 1980. Nouvelles découvertesde vertébrés maestrichtiensdans le gise- saurids have not yet been identified in Europe, but a ment de Fox-Amphoux (Var). 8ème Réunion Annuelle des maniraptoran, possibly a troodontid, has been repor- Sciencesde la Terre : 83. ted from the Early Cretaceous of the Isle of Wight BUFFETAUT, E. & LE LOEUFF, J. I99I. Late Cretaceousdinosaur (Howse and Milner 1993),,suggesting that this clade faunas of Europe : some correlation problems. Cretaceous could be of Euramerican origin. Lisboasaurus from Research,12 : 159-176 the Upper of Portugal, once considered as a MECHIN, P. and MECHIN- SALESSX A. 1995. A large maniraptoran by Milner and Evans (199I), seems to French Cretaceousbird. Nature, 377 : 110. be a peculiar crocodilian (Buscalioni and Ortega BUSCALIONI, A. D. &. ORTEGA, F. 1995. Crocodylomorpha ; 1995). Dromaeosaurids are known from the Early pp. 59-61. In NIEVES-MELENDEZ, M. (ed.) Las Hoyas, a Cretaceous of North America (Deinonychus, lacustrine Konservat-Lagerstâtte,Cuenca, Spain, I I Inte rnational ) and the Late Cretaceous of North Symposium on Lithographic limestones Field trip guide book. America (Dromaeosaltrlts, Saurornitholestes),, CURRIE, P. J. & RUSSELL, D. A. 1988. Osteology and relation ships of Chirostenotespergracilis (, Europe (?Elopteryx, Variraptor) and Asia Theropoda)from the Judith River (Oldman) Formation of Alberta, Canada. (VelociraptoaAdasaurus, Hulsanpes).They probably Canadian Journal of Earth Sciences,25 : 972-986. evolved in Euramerica at the beginning of the DOUBLIER, 1842. Ossementsde saurien du terrain tertiaire du Var. Cretaceous,and then dispersed into Asia via a land Bulletin de la Sociétégéologique de France, 13 : 449. route across the Bering region which appeared bet- GAUTHIER, J. 1986. Saurischian monophyly and the origin of ween North America and Asia in the Late Early birds. In : PADIAN, K. (ed.) The origin of birds and the evolu- tion of flight. Memoirs of the Cretaceous (Russell 1993). By this time, Europe and Califurnia Academy of Sciences, 3 : 1-55. North America had possibly become distinct palaeo- HOLTZ, T. R. Jr. 1994. The phylogenetic position of the bioprovinces (cf. Le Loeuff I99I; 1998) and the : Implications for theropod systematics. European dromaeosaurids subsequently evolved in Journal of ,6S: 1100-IIl7. isolation. HOWSE, S. C. B. &. MILNER, A. R. 1993. Ornithodesmus- a Maniraptoran theropod from the Lower Cretaceousof the Isle of Wight, England. Palaeontology,36 : 425-431. LAPPARENT, A. F. de 1947. Les Dinosauriens du Crétacêsupérieur ACKNOWLEDGEMENTS. du midi de la France. Mémoires de la Société géologique de France,26,4,56 : I-54. We thank the discoverers of the material, Patrick LE LOEUFfl J. 1991.The Campano-Maastrichtianvertebrate faunas and Annie Méchin, whose field work in Provence has from Southern Europe and their relationships with other faunas greatly improved our knowledge of Late Cretaceous in the world : palaeobiogeographicalimplications. Cretaceous Research,12 : dinosaurs. We also thank the owners of the land, M. 93-II4. -1998. Evolution paléobiogéographiquedes faunes de and Mme Patrick Vimont who kindly authorized the vertébrés continentaux du Jurassique supérieur à la fin du excavations,and H.D. Sues (Toronto) who provided Crétacé. Mémoire d'habilitation à diriger des recherches, illustrations of the Saurornitholestes sacrum. Université Paul Sabatier,Toulouse. Tome 1 : 1-68.

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-BUFFETAIIT, E.; MECHIN, P. &. MECHIN- WESTPHAL, F. & DURAND, J.P. 1990. Magnétostratigraphiedes SALESSY, A. 1992.The first record of dromaeosauriddinosaurs sériescontinentales fluvio-lacustres du Crétacésupérieur dans le (Saurischia, Theropoda) in the Maastrichtian of Southern synclinal de I'Arc (région d'Aix-en-Provence,France) . Bulletin Europe : palaeobiogeographicalimplications. Bulletin de la de la Sociétégéologique de France, (8), 6 : 609-620. Sociétégéologique de France, 163 : 337-343. MAKOVICKX P. J. 1995. Phylogenetic aspects of the vertebral morphology of (Dinosauria : Theropoda). Unpublished M. Sc. Thesis, Geological Institute, Copenhagen University. MARSH, O.C. 1881.Classification of the Dinosauria.American Journal of Science,Series 3, 23 : 81-86. MATHERON, P. 1891. Sur les animaux vertébrésdans les couches d'eau douce crétacéesdu midi de la France. Comptes-rendusde l'Association française pour l'Avancementdes Sciences,20 : 382-383. MATTHEW, W. D. & BROWN, B. 1922. The family Deinodontidae, with a notice of a new genusfrom the Cretaceous of Alberta. Bulletin of the American Museum of Natural Histor!, 46 : 367-385. MILNER, A. R. & EVANS, S. E. 1991.The Upper Jurassicdiapsid Lisboasaurus estesi - a maniraptorantheropod. Palaeontology, 34 :503-513. OSBORN, H. F. 1903.The reptilian subclassesSynapsida and Diapsida and the history of the Diaptosauria,Memoirs of the American Museum of Natural History, | : 449-507" L924. Three new Theropoda, zone) central Mongoha. American Museum Novitqtes, 144 : l-I2. OSMOLSKA, H. 1982. Hulsanpes perlei n. g. n. sp" (, Saurischia, Dinosauria) from the Upper Cretaceous Barun Goyot Formation of Mongolia. Neues Jahrbuch fii, Geologie und Palciontologie, Monatshefte : 440-448. OSTROM, J. H. 1969. Osteology of Deinonychus antirchopus, an unusual theropod from the lower Cretaceous of Montana. Bulletin of the PeabodyMuseum of Natural History, 30 : 1-165. I97 6. On a new specimenof the Lower Cretaceous theropod dinosaw Deinonychus antirrhopus. Breviora, 439 : l-10. 1990. Dromaeosauridae. pp. 269-279. In V/EISHAMPEL, D.8., DODSON, p. & OSMOLSKA, H. (Eds) The Dinosauria, University of California Press. OWEN, R. 1842.Report on British reptiles.Part lI. Reports on the British Association for the Advancement of Science, I84l : 60-294. PANESCORSE, F. I87l. Etude sur les phosphatesde chaux et les coprolithesfossiles du Var C. & A. Latil, Draguignan : I-32. RUSSELL, D. A. 1993. The role of Central Asia in dinosaurian biogeography. Canadian Journal of Earth Sciences,30, 2002-2012. & DONG ZHI}I.{ING 1993. A nearly complete Note reçue le 3l-07-1998 acceptéele 15-08-1998 skeleton of a new troodontid dinosaur from the Early Cretaceous of the Ordos Basin, Inner Mongolia, People'sRepublic of China. Canadian Journal of Eqrth Sciences,30 :2163-2173. SUES, H. D. 1978. A new small theropod from the Judith River Formation (Campanian)of Alberta, Canada.Zoological Journal of the Linnean Societyof London, 62: 381-400.

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