Journal of Vertebrate Paleontology 33(1):224–228, January 2013 © 2013 by the Society of Vertebrate Paleontology SHORT COMMUNICATION A PATHOLOGICAL TAIL IN A BASAL SAUROPODOMORPH DINOSAUR FROM SOUTH AFRICA: EVIDENCE OF TRAUMATIC AMPUTATION? RICHARD J. BUTLER, *,1 ADAM M. YATES, 2,3 OLIVER W. M. RAUHUT, 1,4 and CHRISTIAN FOTH 4 ; 1 GeoBio-Center, Ludwig-Maximilians-Universit ¨ at M ¨ unchen, Richard-Wagner-Straße 10, D-80333 Munich, Germany, r.butler@lrz.uni-muenchen.de; 2 Bernard Price Institute, University of the Witwatersrand, Johannesburg 2050, South Africa; 3 Museum of Central Australia, Araluen Cultural Precinct, P.O. Box 3521, Alice Springs, Northern Territory 0871, Australia; 4 Bayerische Staatssammlung f ¨ ur Pal ¨ aontologie und Geologie and Department of Earth and Environmental Sciences, Ludwig-Maximilians-Universit ¨ at M ¨ unchen, Richard-Wagner-Straße 10, D-80333 Munich, Germany SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Paleopathology, the study of fossilized evidence of ancient an- imal disease and traumatic injury, has great potential to pro- vide insights into the paleobiology and life histories of extinct taxa, as well as interspecific and intraspecific interactions such as predator-prey relationships. Recent years have seen a grow- ing focus on the study of pathologies among Mesozoic non-avian dinosaurs (e.g., Tanke and Rothschild, 1997, 2002, 2010; Farke and O’Connor, 2007; Witzmann et al., 2008, 2011; Wolff et al., 2009). One particular subset of paleopathologies are amputa- tions or truncations, the loss of body extremities (e.g., distal parts of fore- and hind limbs, distal tail) as a result of, or following, trauma. Although there is evidence for amputations of dinosaur phalanges and distal tail segments (Tanke and Rothschild, 2002), such injuries have rarely been documented in detail. Tanke and Rothschild (2002:82) mentioned the existence of a hadrosaur that lost the distal 30 cm of the tail, with fusion of the remaining dis- tal caudal vertebrae into a solid bone mass, but this specimen has never been described or figured. Farke and O’Connor (2007) doc- umented a truncated caudal series in a specimen of the theropod Majungasaurus that they interpreted as pathological but not un- ambiguously traumatic (see also Tanke and Rothschild, 2010). We here report a partial skeleton of a basal sauropodomorph dinosaur from the Early Jurassic of South Africa in which a third instance of tail truncation in a dinosaur is recorded. We interpret this truncation as most likely representing a traumatic amputa- tion that did not result in the immediate death of the animal. Institutional Abbreviations—BP, Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, Jo- hannesburg, South Africa; FMNH, Field Museum of Natural History, Chicago, U.S.A.; ZSM, Zoologische Staatssammlung M¨ unchen, Munich, Germany. GEOLOGICAL SETTING BP/1/6771 was collected in March 2008 by a South African/German/British expedition to the upper Elliot For- mation of Upper Drumbo Farm (30 ◦ 48.675 ′ S, 27 ◦ 43.063 ′ E), Barkly East district, Eastern Cape Province, South Africa. The specimen is a single partial skeleton including an articulated series of posterior dorsal, sacral, and anterior caudal vertebrae, pelvic girdles, and fragments of the proximal hind limbs. To date, only parts of the specimen (ischia, distal caudal series) have been completely prepared, preventing a precise taxonomic identifi- cation, though the available material is in general agreement with the morphology of Massospondylus, the most common sauropodomorph from the upper Elliot Formation. BP/1/6771 represents an individual with an estimated body length (assuming a complete tail) of 6 m. Thus, if the taxonomic identification can * Corresponding author. be confirmed, this specimen would be one of the largest individ- uals of Massospondylus known and most probably represents an adult individual. Field excavation and subsequent preparation of the distal caudal series revealed that only 25 caudal vertebrae are present, with the terminal three caudal vertebrae pathologically fused together (Supplementary Data, Fig. S1). At present, no other examples of caudal pathologies have been documented in basal sauropodomorphs from the Elliot Formation. The precise age of the upper Elliot Formation is poorly con- strained, but falls within the Early Jurassic. Although often cited as Hettangian or Sinemurian in age (e.g., Knoll, 2005), an alter- native suggestion is that the formation may be as young as Pliens- bachian or Toarcian (Yates et al., 2004). Although Massospondy- lus appears to be by far the most common sauropodomorph from the upper Elliot Formation (Sues et al., 2004; Barrett, 2009; Reisz et al., 2010), a range of other sauropodomorphs are also known (Vasconcelos and Yates, 2004; Yates et al., 2004, 2010, 2011; Knoll, 2010). MATERIALS AND METHODS The fused distal three vertebrae of BP/1/6771 were scanned using a Nikon Metrology XTH 225/320 LC computed tomogra- phy (CT) system (Microfocus CT facility of the Palaeosciences Centre, University of the Witwatersrand, Johannesburg) with an isotropic voxel size of 66.7 microns (140 kV, 260 μA, 1.2 mm 3 , 3 frames averaged in step-by-step mode, 8000 projections of 0.5 s over 360 ◦ , algorithmic correction of beam hardening). The three-dimensional (3D) processing of the 16 bits data was per- formed using VGStudio Max 2.1 (Volume Graphics, Heidelberg, Germany). This software was also used to produce external ren- derings and anaglyph stereo images (Fig. 1; Supplementary Data, Figs. S2–S5). CT data are reposited at the University of the Wit- watersrand. DESCRIPTION The prepared part of the distal caudal series includes eight ver- tebrae that are preserved in two sets: the first set (Fig. 1A) con- sists of caudals 18–22 in articulation with chevrons, although only the posterior half of caudal 18 is preserved and caudal 22 was badly damaged sometime between initial exposure and final col- lection and is now missing most of its centrum, with only parts of the neural arch preserved. These caudal vertebrae are extremely similar in morphology to those of other basal sauropodomorphs (e.g., Young, 1941), and show no signs of lesions. The second set (Fig. 1B–E; Figs. S2–S5) consists of caudals 23–25, which are fused together and overgrown by a large area of what appears to be reactive bone. Whereas the entire tail up to this point was found in perfect articulation (with all vertebrae and chevrons in place), no additional vertebrae beyond caudal 25 were recovered 224 Downloaded by [Society of Vertebrate Paleontology ] at 03:45 09 January 2013