Osteology of Zalmoxes Shqiperorum (Dinosauria, Ornithopoda), Based on New Specimens from the Upper Cretaceous of Na˘ Lat,-Vad (Romania)
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Osteology of Zalmoxes shqiperorum (Dinosauria, Ornithopoda), based on new specimens from the Upper Cretaceous of Na˘ lat,-Vad (Romania) Pascal GODEFROIT Département de Paléontologie, Institut royal des Sciences naturelles de Belgique, 29 rue Vautier, B-1000 Bruxelles (Belgium) [email protected] Vlad CODREA Catedra de Geologie, Facultatea de Biologie şi Geologie, Universitatea din Babes-Bolyai, 1 Kogalniceanu st., RO-3400 Cluj-Napoca (Romania) [email protected] David B. WEISHAMPEL Center for Functional Anatomy & Evolution, School of Medicine, Johns Hopkins University, 1830 E Monument st. RM 303, Baltimore MD 21205 (USA) [email protected] Godefroit P., Codrea V. & Weishampel D. B. 2009. — Osteology of Zalmoxes shqiperorum (Dinosauria, Ornithopoda), based on new specimens from the Upper Cretaceous of Na˘ lat,- Vad (Romania). Geodiversitas 31 (3) : 525-553. ABSTRACT Nălaţ-Vad is a new fossil locality discovered in 2002 in the Sănpetru Formation (Maastrichtian, Late Cretaceous) of the Haţeg Basin (Transylvania, Romania). Th is site has, among others, yielded the most complete skeleton that can be referred to the ornithopods dinosaur Zalmoxes shqiperorum Weishampel, Jianu, Cziki & Norman, 2003, but also isolated elements belonging to both juveniles and adult individuals. Th is material provides new information about the anatomy KEY WORDS Dinosauria, of Z. shqiperorum, and about the inter- and intraspecifi c variability within Zal- Ornithopoda, moxes. Zalmoxes robustus (Nopsca, 1902) and Z. shqiperorum were apparently Zalmoxes shqiperorum, sympatric species in Transylvania by latest Cretaceous time. Th e co-existence Upper Cretaceous, Haţeg Basin, in the same locality of two closely-related species is not an isolated case among sympatry. ornithopod dinosaurs. GEODIVERSITAS • 2009 • 31 (3) © Publications Scientifi ques du Muséum national d’Histoire naturelle, Paris. www.geodiversitas.com 525 Godefroit P. et al. RÉSUMÉ Ostéologie de Zalmoxes shqiperorum (Dinosauria, Ornithopoda), d’après de nou- veaux spécimens du Crétacé supérieur de Nălaţ-Vad (Roumanie). Nălaţ-Vad est un nouveau site fossilifère découvert en 2002 dans la Formation de Sănpetru (Maastrichtien, Crétacé supérieur) du bassin de Haţeg (Transylvanie, Roumanie). Ce site a notamment livré le squelette le plus complet à ce jour pou- vant être attribué au dinosaure ornithopode Zalmoxes shqiperorum Weishampel, Jianu, Cziki & Norman, 2003, mais également des ossements isolés appartenant à des individus juvéniles et adultes. Ce matériel apporte de nouvelles informations MOTS CLÉS Dinosauria, sur l’anatomie de Z. shqiperorum, mais également sur la variabilité inter- et intra- Ornithopoda, spécifi que au sein même du genre Zalmoxes. Zalmoxes robustus (Nopsca, 1902) et Zalmoxes shqiperorum, Z. shqiperorum étaient apparemment des espèces sympatriques en Transylvanie Crétacé supérieur, bassin de Haţeg, au Crétacé supérieur. La coexistence dans une même localité de deux espèces sympatrie. proches n’est pas un cas isolé chez les dinosaures ornithopodes. INTRODUCTION Mochlodon robustum Nopcsa, 1902 (Nopcsa 1902, 1904). He later suggested that Mochlodon might be Although Rhabdodontidae probably comprises identical to Rhabdodon and that sexual dimorphism the most abundant dinosaurs from the Upper might be responsible for the observed diff erences Cretaceous of Europe, these medium-sized ornitho- between the two forms (Nopcsa 1915, 1929). pods remained poorly understood until recently. Ösi (2004) reported rhabdodontid fossils in the Rhabdodon priscus Matheron, 1869 was described Upper Cretaceous of Hungary. Weishampel et al. from fragmentary material discovered in the lower (2003) recently reviewed the rhabdodontid mate- Maastrichtian of La Nerthe (Bouches-du-Rhône, rial from Transylvania, and referred it to as a new France). Additional material from diff erent locali- genus, Zalmoxes. Th ey distinguished two species: ties in southern France, referred to as R. priscus, Z. robustus (Nopcsa, 1902), known from abun- was described later by Lapparent (1947), Garcia dant skull and postcranial material, and the more et al. (1999), Pincemaille-Quillévéré (2002), and poorly known species Z. shqiperorum Weishampel, Pincemaille-Quillévéré et al. (2006). Buff etaut & Jianu, Cziki & Norman, 2003. Both species are Le Loeuff (1991) described Rhabdodon septimani- known from several localities in the Haţeg Basin, cus from a dentary discovered in the Campano- but also from the Vintu de Jos area (Fig. 1). Th e Maastrichtian of Montmouliers (Hérault, France). holotype of Z. shqiperorum (BMNH R4900) is a Rhabdodon Matheron, 1869 specimens have also single incomplete adult individual. Much of the been described in diff erent Campano-Maastrichtian referred material pertains to a partially associated localities from northern Spain (Pereda-Suberbiola & skeleton of a juvenile, which includes most of the Sanz 1999). Bunzel (1871) described Iguanodon pelvis and associated dorsal, sacral and caudal ver- suessi from the Upper Cretaceous of Niederöster- tebrae (FGGUB R1087-1133 and R1355-1357). reich (Austria). Seeley (1881) subsequently created From the skull of Z. shqiperorum, only the dentary the genus Mochlodon to include this species. In the is known to date. Both the fore- and hindlimbs beginning of the 20th century, Nopcsa described were also incompletely known. Sachs & Hornung important ornithopod material from the Upper (2006) referred specimens discovered in Austria Cretaceous of the Haţeg Basin in Transylvania. Part to Zalmoxes. of this material was referred to Mochlodon suessi New material that can be referred to as Z. shqipero- Seeley, 1881 and another part to a new species rum was discovered in 2002 at Nălaţ-Vad, a new 526 GEODIVERSITAS • 2009 • 31 (3) Osteology of Zalmoxes shqiperorum (Dinosauria, Ornithopoda) from Romania locality in the Sănpetru Formation of the Haţeg Metaliferi mountains Mures Basin. Th e new material, housed in the Catedra de Cugir Geologie, Facultatea de Biologie şi Geologie, Uni- Orastie versitatea din Babes-Bolyai (Cluj-Napoca, Roma- Poiana Rusca mountains nia), includes the most complete skeleton that can Orastie hills II e be referred to date to this taxon (UBB NVZ1), but Govajdia rasti also isolated elements belonging to both juvenile and O Sureanu Strei Hunedoara hills adult individuals. It provides new information about mountains the anatomy of Z. shqiperorum, and about the inter- Cerna Valioara Tustea Hateg‚ and intraspecifi c variability within Zalmoxes. Rusca Densus Nalat˘ ‚ Vad Th e aim of the present paper is to complete the osteo- I Montana˘ Totesti e logical description of Z. shqiperorum, whose skeleton Sanpetru˘ Pui Mar is scarcely known so far, on the basis of the newly- III Râul l discovered material from Nălaţ-Vad. Th e diagnoses of Petrosani Cluj-Napoca Sibise ‚ Barbat both Zalmoxes and Z. shqiperorum and the apparent IV sympatry of two closely-related species of medium- Hateg‚ Retezat Bucharest mountains Jiul de Vest sized herbivorous dinosaurs will be discussed. 15 km ABBREVIATIONS FIG. 1. — Geographical location of the different localities that have BMNH Department of Palaeontology, Natural His- yielded fossils of Zalmoxes robustus (Nopsca, 1902) (black stars) tory Museum, London; and Z. shqiperorum Weishampel, Jianu, Cziki & Norman, 2003 (white FGGUB Facultatea de Geologie şi Geofi zics, Univer- stars) in Haţeg and surrounding basins (Romania): I, Rusca Montană sitatea din Bucareşti; Basin; II, Strei Basin; III, Haţeg Basin; IV, Petroşani Basin. UBB Catedra de Geologie, Facultatea de Biologie şi Geologie, Universitatea din Babes-Bolyai, Cluj-Napoca. Numerous palaeosols developed within these de- posits, as indicated by the presence of calcretes and GEOLOGICAL SETTING the reddish coloration of the sediments (Smith et al. 2002; Van Itterbeeck et al. 2004). Dinosaur eggs were Th e Nălaţ-Vad locality is a newly discovered exposure found in these calcretes, but they are less numerous situated in the bedding of the Raul Mare River between than at Toteşti-Baraj. On the other hand, vertebrate the villages of Nălaţ and Vad. Usually, the water fl ow remains are by far more numerous at Nălaţ-Vad. Al- covers nearly the entire exposure, so that the excavation though isolated bones were randomly found in the conditions are particularly hard. Th e strike of the layers entire locality, three pockets have yielded concentrated (N40E75N) does not signifi cantly diff ers from the vertebrate remains. A pocket with microvertebrates strike of the Toteşti-Baraj locality (Codrea et al. 2002), consists of a limestone mainly composed of eggshell situated 3 km upstream. According to the geological debris, a so-called coquina that grades into black- map of the area, the outcropping sediments belong coloured marls that is less enriched in egg shells. to the Sănpetru Formation (Grigorescu 1983, 1992; Both the marl and limestones are extremely rich in Grigorescu et al. 1999; Van Itterbeeck et al. 2004). micro vertebrate remains, mainly mammals, birds Palaeomagnetic studies suggest that this formation and small theropods. Th e second pocket was rich should entirely belong to the lower Maastrichtian in sauropod bones. Th e third pocket has yielded (Panaiotu & Panaiotu 2002). Th e facies assemblage disarticulated Zalmoxes bones, apparently belonging at Nălaţ-Vad indicates a fl uvial palaeoenvironment to a single individual (UBB NVZ1). However, one with sandy channel infi lls and dominantly black to slender quadrate from this pocket apparently does reddish-brown overbank fi