Anais da Academia Brasileira de Ciências ISSN: 0001-3765 [email protected] Academia Brasileira de Ciências Brasil MATEUS, OCTÁVIO; JACOBS, LOUIS L.; SCHULP, ANNE S.; POLCYN, MICHAEL J.; TAVARES, TATIANA S.; BUTA NETO, ANDRÉ; MORAIS, MARIA LUÍSA; ANTUNES, MIGUEL T. Angolatitan adamastor, a new sauropod dinosaur and the first record from Angola Anais da Academia Brasileira de Ciências, vol. 83, núm. 1, marzo, 2011, pp. 221-233 Academia Brasileira de Ciências Rio de Janeiro, Brasil Available in: http://www.redalyc.org/articulo.oa?id=32717681011 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative “main” — 2011/2/10 — 15:47 — page 221 — #1 Anais da Academia Brasileira de Ciências (2011) 83(1): 221-233 (Annals of the Brazilian Academy of Sciences) Printed version ISSN 0001-3765 / Online version ISSN 1678-2690 www.scielo.br/aabc Angolatitan adamastor, a new sauropod dinosaur and the first record from Angola , OCTÁVIO MATEUS1 2, LOUIS L. JACOBS3, ANNE S. SCHULP4, MICHAEL J. POLCYN3, TATIANA S. TAVARES5, ANDRÉ BUTA NETO5, MARIA LUÍSA MORAIS5 and MIGUEL T. ANTUNES6 1CICEGe, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal 2Museu da Lourinhã, Rua João Luis de Moura, 2530-157 Lourinhã, Portugal 3Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX, 75275, USA 4Natuurhistorisch Museum Maastricht, de Bosquetplein 6-7, NL6211 KJ Maastricht, The Netherlands 5Geology Department, Universidade Agostinho Neto, Av. 4 Fevereiro, Luanda, Angola 6Academia de Ciências de Lisboa, Rua da Academia das Ciências, 19, 1242-122 Lisboa, Portugal Manuscript received on October 19, 2009; accepted for publication on June 21, 2010 ABSTRACT A forelimb of a new sauropod dinosaur (Angolatitan adamastor n. gen. et sp.) from the Late Turonian of Iembe (Bengo Province) represents the first dinosaur discovery in Angola, and is one of the few occurrences of sauropod dinosaurs in sub-Saharan Africa collected with good chronological controls. The marginal marine sediments yielding the specimen are reported to be late Turonian in age and, thus it represents a non-titanosaurian sauropod in sub-Saharan Africa at a time taken to be dominated by titanosaurian forms. Moreover, Angolatitan adamastor is the only basal Somphospondyli known in the Late Cretaceous which implies in the existence of relict forms in Africa. Key words: Angola, Cretaceous, Turonian, Dinosaurs, Sauropoda, Angolatitan. INTRODUCTION OM), of the new taxon reported here. Follow-up exca- vations were performed in May and August 2006. To Although very rich in Cretaceous vertebrates, Angola our knowledge, it was the only systematic prospecting has remained unexplored in recent decades. Beginning for fossil vertebrates in this area since 1960 by M. Telles in 2005, the field work conducted by the PaleoAngola Antunes (in September) and M. Mascarenhas Neto. Project has significantly enhanced the palaeontological While the lush vegetation in most inland areas record of the Cretaceous of Angola (Jacobs et al. 2006, precludes fossil prospecting, the exposures along the 2009a, b, Polcyn et al. 2009, Mateus et al. 2008, Schulp Atlantic coastline in Ambriz municipality allows sys- et al. 2008). The PaleoAngola Project mounted the tematic prospecting. The material collected by the first systematic paleontological expeditions that have PaleoAngola Project is largely housed at Museu Geo- been conducted since the early 1960s, when Miguel Tel- lógico da Universidade Agostinho Neto (MGUAN) in les Antunes performed an extensive and systematic sur- Luanda, while some of the collected mosasaur, plesio- vey on the Angolan fossil vertebrate fauna the most rel- saur, pterosaur, and turtle specimens are temporarily evant work published in 1964 (Antunes 1964). In May housed at Museu da Lourinhã (ML), Portugal, and 2005 we (O.M. and L.J.) prospected the coastal area near Southern Methodist University (SMU) in Dallas, to Iembe which resulted in the discovery, in May, 25th (by be returned to Angola after preparation and study. Proceedings of the Third Gondwanan Dinosaur Symposium Correspondence to: Octávio Mateus E-mail: [email protected] An Acad Bras Cienc (2011) 83 (1) “main” — 2011/2/10 — 15:47 — page 222 — #2 222 OCTÁVIO MATEUS et al. GEOLOGY AND ASSOCIATED FAUNA The term ‘Tadi beds’ was first coined in the 1960 unpub- lished study of G. Brognon , G. Verrier, and R Thiers “Géologie du Bassin du Cuanza et du Bas-Congo” from the “Missão de Pesquisas de Petróleo Petrofina”. It was accepted and used by Antunes (1964) and Antunes and Cappetta (2002). The original study considered the ‘Tadi Beds’ to represent the base of the ‘Senonian’ (= Conia- cian), but the fish fauna led Antunes (1961, 1964: 56)to consider the Tadi Beds to be of late Turonian age. In a revision of the Cretaceous selachians of Angola, Antu- nes and Cappetta (2002: 95) reconfirm the late Turonian age of these beds, and place them in the ‘Itombe Forma- tion’ (see also Jacobs et al. 2006). The Tadi Beds are about 50 m thick (Antunes 1964: 56). G. Brognon et al. (cited in Antunes 1964: 56) provide a list of the inver- tebrate fauna, including the ammonite genera Hemitis- sotia, Romaniceras and Pachydiscus, and echinoderms. The fish and shark fauna (Antunes and Cappetta 2002: 95) includes Hexanchus cf. microdon, Ptychodus mor- Fig. 1 – Map of Angola, showing the Tadi site (star; 08◦S/13◦E) and toni, P. cf. paucisulcatus, P. whipplei, Scapanorhynchus the distribution of Cretaceous strata (grey) in Angola. raphiodon, S. cf. lewesii, Cretodus semiplicatus, Cre- todus sp., Cretoxyrhina mantelli, Paranomotodon an- ETYMOLOGY gustidens, Squalicorax falcatus, Squalicorax sp., On- Angolatitan means Angolan giant. Adamastor was a chosaurus pharaoh, and Enchodus cf. elegans. mythological sea giant from the South Atlantic feared The tetrapod fauna from the Iembe locality (An- by the Portuguese sailors. tunes 1964, Jacobs et al. 2006; and new unpublished data) includes an eucryptodiran turtle Angolachelys GENERIC AND SPECIFIC DIAGNOSIS mbaxi (Mateus et al. 2009), the mosasaurs Angolasau- Titanosauriform sauropod with: posteroventral emin- rus bocagei Antunes 1964 (see also Polcyn et al. 2009) ence in scapula in the proximal one-quarter, anterior and Tylosaurus iembeensis (Antunes 1964, Lingham- to the acromial ridge; acute medioproximal margin of Soliar 1992), Plesiosauria indet., and the sauropod ma- humerus; and rectangular lateral corner of proximal hu- terial described here. The discovery here reported is the merus; proximal outline of the ulna with anteromedial first dinosaur and the first Cretaceous terrestrial animal ridge (process); posterior facet of the distal epiphysis from Angola. of metacarpal I with two small splint-like projections (Figs. 3 and 5). SYSTEMATICS PALEONTOLOGY TYPE LOCALITY AND HORIZON Dinosauria Owen, 1842 Tadi, near Iembe, Tábi community, municipality of Am- Sauropoda Marsh, 1878 briz, Bengo Province, Angola. The precise coordinates Neosauropoda Bonaparte, 1986 of collecting sites are on file at the participating institu- Titanosauriformes Salgado et al., 1997 tions. Somphospondyli Wilson and Sereno, 1998 Tadi Beds, Itombe Formation, Late Turonian Angolatitan adamastor n. gen., n. sp. (around 90 M.a.), Late Cretaceous. An Acad Bras Cienc (2011) 83 (1) “main” — 2011/2/10 — 15:47 — page 223 — #3 NEW SAUROPOD DINOSAUR FROM ANGOLA 223 Fig. 2 – Summary of the geology of the Cretaceous of Kwanza Basin (Angola) based on Brownfield and Charpentier (2006) and Coward etal. (1999). MATERIAL However, this could be a case of taphonomical distor- tion. The proximal end is incomplete, but does not seem The material includes a partial right forelimb including very expanded. The scapular blade is 16.5 cm, with the the scapula, humerus, ulna, radius and metacarpals I, III, ventral supraglenoid expansion just above it, and 24 cm and IV (Table I). All material described here is curated on the maximum dorsal expansion. The ventral supra- at Museu de Geologia da Universidade Agostinho Neto glenoid expansion is 65 cm in its maximum anteropos- – PaleoAngola Project, Luanda, Angola (MGUAN-PA), terior width, therefore representing nearly four times and temporarily registered under field number MGUAN- the minimum width of the blade. For the description, PA-003 (replicas will be housed at Museu da Lourinhã, the orientation of the scapula adopted here is with the Portugal, and at Southern Methodist University, USA). scapular blade in a vertical dorsal position as in Romer (1956). DESCRIPTION The blade is rectangular in cross section, with thick- The scapula is missing its posterior end and part of er anterior margin. The anterior margin (acromial side) its proximal expansion. The preserved length is 95 cm, is bowed anteriorly in lateral view, while the posterior but it is estimated to have been 105 cm if complete. The rim is nearly straight, except for the ventral portion that scapula is overall straight rather than bowed medially. expands posteriorly. The acromion strongly projects An Acad Bras Cienc (2011) 83 (1) “main” — 2011/2/10 — 15:47 — page 224 — #4 224 OCTÁVIO MATEUS et al. Fig. 3 – Angolatitan adamastor n. gen. et sp., A) right scapula in medial view; B) right humerus in proximal(a), anterior (b), distal (c), medial (d), and posterior (e) views. Autapomorphic features: 1, posteroventral eminence in scapula in the proximal one-quarter, anterior to the acromial ridge; 2, acute medioproximal margin of humerus; and 3, rectangular lateral corner of proximal humerus. anteriorly, forming a gentle curve in its anterodorsal ally glenoid is apomorphic of Somphospondyli accord- corner due to the absence of the dorsal hook. ing to Wilson 2002 (character 153). The medial surface is gently concave in all its The ventroposterior margin of the scapula, adja- extension, except in a small (ca. 6 cm) shallow bump cent to the glenoid, projects posteriorly and has a small placed at the anterior part at the base of the scapular (ca.