Ornithischian and theropod dinosaurs were morphologically diverse during the Cretaceous. In contrast, sauropods were relatively more conservative. The anatomy of Bonitasaura salgadoi, a new 9-m titanosaurian sauropod from Upper Cretaceous beds of Patagonia, suggests that sauropod anatomical diversity would have included unexpected items. Its unusual, rectangular lower jaw possesses narrow, anteriorly restricted teeth and shows evidence of a sharp keratinous sheath over the non-dentigerous region that probably worked to guillotine plant material. This discovery definitely demonstrates that titanosaurs acquired a mandibular configuration similar to that of some basal diplodocoids, as had already been suggested by the lower jaw of the controversial genus Antarctosaurus. This oral configuration, plus the beak-like structure and the skull shape, resemble some traits more commonly seen in Laurasian ornithischians, mostly unexpressed in southern continents. A high sauropod morphological diversity seems to be in agreement with the poorly represented ornithischian clades of the southern hemisphere.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Price excludes VAT (USA)
Tax calculation will be finalised during checkout.
Apesteguía S, Gallina PA (2002) A new non-saltasaurine titanosaur from ‘Rancho de Ávila’ (Río Negro) in the Bajo de la Carpa-Anacleto formations boundary. Ameghiniana 40:51R
Bakker RT (1986) The dinosaur heresies: new theories unlocking the mystery of the dinosaurs and their extinction. Zebra Books
Calvo JO (1994) Jaw mechanics in sauropod dinosaurs. Gaia 10:183–193
Calvo JO, González Riga, BJ (2003) Rinconsaurus caudamirus gen. et sp. nov., a new titanosaurid (Dinosauria, Sauropoda) from the Late Cretaceous of Patagonia, Argentina. Rev Geol Chile 30:333–353
Coria RA, Chiappe LM (2001) Tooth replacement in a sauropod maxilla from the Upper Cretaceous of Patagonia, Argentina. Ameghiniana 38:463–466
Curry Rogers K, Forster CA (2004) The skull of Rapetosaurus krausei (Sauropoda: Titanosauria) from the Late Cretaceous of Madagascar. J Vert Paleontol 24: 121–144
Gallina PA, Apesteguía S, Novas FE (2002) ¿Un elefante bajo la alfombra? Los Rebbachisauridae (Sauropoda, Diplodocimorpha) del Cretácico de Gondwana. Nuevas evidencias en “La Buitrera” (Fm. Candeleros), provincia de Río Negro. Ameghiniana 39:10R
Holland WJ (1906) The osteology of Diplodocus Marsh. Mem Carn Mus 2:225–264
Huene F von (1929) Los saurisquios y ornitisquios del Cretáceo Argentino. Ann Mus La Plata Sect Paleontol 2:1–196
Hugo C, Leanza HA (1999) Hoja Geológica 3969-IV, General Roca, provincias del Neuquén y Río Negro. Inst Geol Rec Nat SEGEMAR 3969-IV, pp 1–95
Jacobs L, Winkler DA, Downs WR, Gomani EM (1993) New material of an Early Cretaceous titanosaurid sauropod dinosaur from Malawi. Palaeontology 36:523–534
Martínez R (1998) An articulated skull and neck of Sauropoda (Dinosauria: Saurischia) from the Upper Cretaceous of Central Patagonia, Argentina. J Vert Paleontol 18:61A
Morris WJ (1970) Hadrosaurian dinosaur bills: morphology and function. Contrib Sci 193:1–14
Norell MA, Makovicky PJ, Currie PJ (2001) The beaks of ostrich dinosaurs. Nature 412:873
Nowinski A (1971) Nemegtosaurus mongoliensis n. gen., n. sp. (Sauropoda) from the Uppermost Cretaceous of Mongolia. Palaeontol Polon 25:57–81
Paul GS (1984) The segnosaurian dinosaurs: relics of the prosauropod–ornithischian transition? J Vert Paleontol 4:507–515
Powell JE (1979) Sobre una asociación de dinosaurios y otras evidencias de vertebrados de la región de La Candelaria, prov. de Salta, Argentina. Ameghiniana 16:191–204
Powell JE (2003) Revision of the South American titanosaurid dinosaurs: palaeobiological, palaeobiogeographical and phylogenetic aspects. Rec Queen Victoria Mus 111:1–173
Salgado L (2001) Los Saurópodos de Patagonia: sistemática, evolución y paleobiología. Abst II J Int Paleontol Dinos Ent Burgos 2001:139–168
Salgado L, Calvo JO (1997) Evolution of titanosaurid sauropods. II. The cranial evidence. Ameghiniana 34:33–47
Sereno PC, Beck AL, Dutheil DB, Larsson HCE, Lyon GH, Moussa B, Sadleir RW, Sidor CA, Varricchio DJ, Wilson GP, Wilson JA (1999) Cretaceous sauropods from the Sahara and the uneven rate of skeletal evolution among dinosaurs. Science 286:1342–1347
Upchurch P (1999) The phylogenetic relationships of the Nemegtosauridae (Saurischia, Saruopoda). J Vert Paleontol 19:106–125
Wilson JA (2002) Sauropod dinosaur phylogeny: critique and cladistic analysis. Zool J Linn Soc 136:217–276
Wilson JA, Carrano MT (1999) Titanosaurs and the origin of ‘wide-gauge’ trackways: a biomechanical and systematic perspective on sauropod locomotion. Paleobiology 25:252–267
Wilson JA, Sereno PC (1998) Early evolution and higher-level phylogeny of sauropod dinosaurs. J Vert Paleontol Mem 5:1–68
The work was supported by the Jurassic Foundation and Paleogenesis. I gratefully acknowledge the assistance of the Pincheira and Ávila families and thank them for their kind help. Thanks to Mr. Parodi for guiding us to the fossil site and to Marcos Zúñiga and the Salinas family for logistics. P.A. Gallina, F.L. Agnolin, G. Lio, L. Gaetano, M. Cardenas, M. de la Fuente, L. Ballarino, F. Pose, are thanked for field support. Thanks to the geologists Hugo Corbela and Hector Leanza for the stratigraphic position of the specimen. I am grateful to J.A. González for illustrations and M. Isasi for preparation. M. Lamanna, J.F. Bonaparte and P.J. Makovicky substantially improved this work with useful comments and critical reviews.
Communicated by G. Mayr
Rights and permissions
About this article
Cite this article
Apesteguía, S. Bonitasaura salgadoi gen. et sp. nov.: a beaked sauropod from the Late Cretaceous of Patagonia. Naturwissenschaften 91, 493–497 (2004). https://doi.org/10.1007/s00114-004-0560-6
- Late Cretaceous
- Theropod Dinosaur
- Southern Continent
- Negro Province