gargantuavis philoinos: giant bird or giant pterosaur?

Journal Identification = ANNPAL Article Identification = 2144 Date: July 8, 2011 Time: 2:32 pm

Annales de Paléontologie 96 (2010) 135–141

Disponible en ligne sur www.sciencedirect.com

Original article

Gargantuavis philoinos: Giant bird or giant pterosaur?

Gargantuavis philoinos : oiseau géant ou ptérosaure géant ?

Eric Buffetaut a,∗, Jean Le Loeuff b

a UMR CNRS 8538, Laboratoire de géologie de l’École Normale Supérieure,24, rue Lhomond, 75231 Paris cedex 05, France

b Musée des dinosaures, 11260 Espéraza, France

Available online 1 July 2011

Abstract

Gargantuavis philoinos was described as a giant terrestrial bird on the basis of various postcranial ele-ments (synsacrum and pelvis, femur) from Late Cretaceous (Campanian-Maastrichtian) localities in SouthernFrance. It has recently been suggested that these remains in fact belong to giant pterosaurs. A detailed compar-ison between bones referred to Gargantuavis and the corresponding skeletal elements of pterosaurs revealsconsiderable differences and confirms the avian nature of Gargantuavis. The broad pelvis of Gargantuavisis similar to that of various extinct graviportal terrestrial birds.© 2011 Elsevier Masson SAS. All rights reserved.

Keywords: Gargantuavis; Aves; Pterosauria; Late Cretaceous; France

Résumé

Gargantuavis philoinos a été décrit comme un oiseau géant terrestre à partir de divers éléments postcrâniens(synsacrum et bassin, fémur) de plusieurs gisements du Crétacé supérieur (Campanien-Maastrichtien) duSud de la France. Il a récemment été suggéré que ces restes appartiennent en fait à des ptérosaures géants. Unecomparaison détaillée entre les os rapportés à Gargantuavis et les éléments squelettiques correspondants deptérosaures révèle des différences considérables et confirme la nature avienne de Gargantuavis. Le bassinélargi de Gargantuavis est similaire à celui de divers oiseaux terrestres éteints de type graviporteur.© 2011 Elsevier Masson SAS. Tous droits réservés.

Mots clés : Gargantuavis ; Aves ; Pterosauria ; Crétacé supérieur ; France

∗ Corresponding author.E-mail address: [email protected] (E. Buffetaut).

0753-3969/$ – see front matter © 2011 Elsevier Masson SAS. All rights reserved.doi:10.1016/j.annpal.2011.05.002

dx.doi.org/10.1016/j.annpal.2011.05.002

mailto:[email protected]

dx.doi.org/10.1016/j.annpal.2011.05.002


136 E. Buffetaut, J. Le Loeuff / Annales de Paléontologie 96 (2010) 135–141

1. Introduction

The presence of a giant bird in the Late Cretaceous of Southern France was first reported byBuffetaut et al. (1995) on the basis of a synsacrum fragment from Fox-Amphoux, in Provence.Subsequently, Buffetaut and Le Loeuff (1998) described a new taxon, Gargantuavis philoinos,on the basis of a pelvis and a referred femur from two Late Cretaceous localities (Campagne-sur-Aude and Villespassans) in Languedoc. All currently known Gargantuavis specimens are fromlocalities of Late Campanian to Early Maastrichtian age. Gargantuavis philoinos was describedas an ostrich-sized bird showing various primitive characters suggesting that it was a relativelybasal, non-ornithurine form.

Although the avian nature of Gargantuavis has been accepted by various authors (e.g. Feduccia,1999; Donaire and López-Martínez, 2009; Paul, 2002; Sarjeant and Currie, 2001), Mayr (2009,p. 21) quoting a personal communication from Worthy, suggested “a possible pterosaurian identityof Gargantuavis”. This suggestion is discussed in the present paper.

2. Purported pterosaur characters in Gargantuavis

The main supposedly pterosaur-like character in Gargantuavis, according to Worthy and Mayr,is the “cranially positioned acetabular foramen” (Mayr, 2009, p. 21). Gargantuavis philoinosindeed has an acetabulum that is located relatively far forward relative to the fused vertebrae ofthe synsacrum. As noted by Buffetaut and Le Loeuff (1998), the acetabulum is in an anteriorposition relative to the synsacrum, being placed at the level of the 3rd and 4th synsacral transverseprocesses. However, this cannot be considered as a pterosaurian character, as pterosaurs do notshow a particularly forward-located acetabulum. For instance, in the large Late Cretaceous genusPteranodon, which, like Gargantuavis, has a synsacrum consisting of 10 fused vertebrae, theacetabulum is located in a very posterior position, at the level of the 7th synsacral vertebra (Eaton,1910; Bennett, 2001). In the nyctosaurid Muzquizopteryx (Frey et al., 2006), the acetabulum isapparently in a somewhat more anterior position, being described as being at the level of the 4th or5th synsacral vertebra, the synsacrum containing at least 8 vertebrae. Nevertheless, the acetabulumof Muzquizopteryx is in a posterior position relative to the pelvis as a whole, as shown by the figuresin Frey et al. (2006). Generally, pterosaurs thus have a posteriorly located acetabulum, relative toboth the synsacrum and to the pelvis in general, because the ilium has a long anterior blade (seeWellnhofer, 1978, for illustrations of pterosaur pelves and synsacra showing this condition). Thisis very different from the condition in Gargantuavis (Fig. 1).

Mayr (2009), p. 21 drew attention to the fact that Gargantuavis remains come from siteswhich also contain pterosaur remains and noted that “the locality [of Gargantuavis] also yieldedremains of very large azhdarchid pterosaurs, whose femur and pelvis are still unknown”. In fact,the Bellevue locality which has yielded the type synsacrum and associated pelvis of Gargantuavisphiloinos has provided only very poorly preserved pterosaur material (Buffetaut, 1998, 2008),which does not indicate very large forms. An azhdarchid humerus (Buffetaut et al., 2006) is knownfrom the locality at Fox-Amphoux which yielded the first specimen of a giant bird from the LateCretaceous of France, but again this humerus does not indicate a giant form. The only reallyhuge azhdarchid specimen (a cervical vertebra suggesting a 9 m wingspan) hitherto reported fromFrance comes from a younger, Late Maastrichtian locality at Mérigon, in Ariège (Buffetaut et al.,1997).

Mayr (2009) contention that the femur and pelvis of very large azhdarchids are still unknown isonly partly correct. A femur of a very large pterosaur from the Maastrichtian of Romania, probably


E. Buffetaut, J. Le Loeuff / Annales de Paléontologie 96 (2010) 135–141 137

Fig. 1. Comparison of the synsacra and pelves of Gargantuavis (A, after Buffetaut and Le Loeuff, 1998) and thegiant pterosaur Pteranodon (B, after Bennett, 2001), in ventral view showing the acetabulum (ac) in cranial positionin Gargantuavis and caudal position in Pteranodon. Scale bar: 50 mm.Comparaison des synsacra et os pelviens de Gargantuavis (A, d’après Buffetaut et Le Loeuff, 1998) et du ptérosaure géantPteranodon (B, d’après Bennett, 2001), en vue ventrale montrant l’acetabulum (ac) en position crâniale chez Gargantuaviset en position caudale chez Pteranodon. Barre d’échelle : 50 mm.

belonging to the giant azhdarchid Hatzegopteryx, was described by Buffetaut et al. (2003). It is anelongate and slender bone (as usual in pterosaurs) which is completely different from the shorterand stockier femur referred to Gargantuavis (Fig. 2). Femur morphology is fairly well knownin azhdarchids, thanks notably to Averianov’s redescription of Azhdarcho (Averianov, 2010).The relatively small articular head, borne by a long slender collum, of the femur of Azhdarcholancicollis is very different from the large head, borne by a short broad collum, of the femurof Gargantuavis philoinos. In Azhdarcho lancicollis, the greater trochanter is a more or lessconical protrusion, whereas in Gargantuavis philoinos it forms a broad flange. The femur of theazhdarchid Zhejiangopterus linaihensis is described as “long, gracile and slightly curved” by Caiand Wei (1994), which is completely different from the condition in Gargantuavis philoinos.

As to the pelvis, it is indeed poorly known in azhdarchids. It is present in a specimen ofZhejiangopterus linhaiensis, an azhdarchid with a wingspan of about 5 m from the Campanian ofChina (Cai & Wei, 1994; Unwin & Lü, 1997). Unfortunately, the pelvis and synsacrum are crushedand show few details. However, the articulated skeleton M1323 shows that the femur meets thepelvis in a caudal, not cranial, position, so the position of the acetabulum was similar to what it isin other pterosaurs, and unlike the condition in Gargantuavis. Averianov (2007) noted that “Thesubstantially flattened posterior dorsal (“lumbar”) vertebrae of Azhdarcho and Aralazhdarcho gen.nov. suggest that they had a wide sacrum (this probably concerns all azhdarchids), in contrastto, for example, Pteranodon spp”. This must be considered as conjectural until better preservedazhdarchid sacra are found. The synsacrum of azhdarchids may have been somewhat different



Fig. 2. The femur of Gargantuavis (A, after Buffetaut and Le Loeuff, 1998) and that of a giant pterosaur (presumably theazhdarchid Hatzegopteryx) from the Late Cretaceous of Romania (B, after Buffetaut et al., 2003), in cranial view. Scalebars: 50 mm.Le fémur de Gargantuavis (A, d’après Buffetaut et Le Loeuff, 1998) et celui d’un ptérosaure géant (vraisemblablementl’azhdarchidé Hatzegopteryx) du Cretacé supérieur de Roumanie (B, d’après Buffetaut et al., 2003), en vue crâniale.Barre d’échelle : 50 mm.

from that of other large pterosaurs, and relatively broad as in Gargantuavis, but the little that isknown about the position of their acetabulum certainly does not suggest that it was in a cranialposition.

3. The broad pelvis of Gargantuavis philoinos and its significance

In addition, Mayr (2009, p. 21), mentions that “the wide pelvis of Gargantuavis is very unlikethe narrow one typically found in large groundbirds (ratites, Gastornithidae, Phorusrhacidae)”.Gargantuavis does have a wide pelvis, as noted by Buffetaut and Le Loeuff (1998), while manylarge groundbirds do have narrow ones. This can clearly be seen in some living ratites, such as Rheaor Struthio (Fig. 3). The extinct phorusrhacids possessed an extremely narrow pelvis (Andrews,1899). Both the above-mentioned ratites and most phorusrhacids are (or were) cursorial forms(Blanco & Jones, 2005), and the narrowness of their pelvis probably reflects adaptations to thistype of locomotion. Not all groundbirds, however, possess such a narrow pelvis. Among ratites,heavily built moas had a pelvis that was much broader than that of running ratites (Fig. 3; seealso Lambrecht, 1933, Fig. 52). As to the Gastornithidae, in Gastornis (= Diatryma), the pelvis isbroad (Matthew & Granger, 1917; Fischer, 1962) rather than narrow, and the acetabulum is in arelatively anterior position. The dromornithids, a family of giant groundbirds from the Cenozoicof Australia, similarly had a broad pelvis: that of Dromornis stirtoni is described as “massive,



Fig. 3. Pelves of the living Rhea (A, Museum of Zoology, Cambridge University) and a stoutly built moa from thePleistocene of New Zealand (B, Muséum National d’Histoire Naturelle, Paris), in dorsal view, illustrating narrow andbroad pelvic morphologies in ratites. Not to scale.Os pelviens de l’actuel Rhea (Museum of Zoology, Cambridge University) et un Moa robuste du Pléistocène de NouvelleZélande (B, Muséum National d’Histoire Naturelle, Paris), en vue dorsale, illustrant les morphologies pelviennes étroiteset larges connues chez les ratites. Sans échelle.

deep and transversely broad posteriorly” (Murray & Vickers-Rich, 2004); the acetabulum is alsolocated in an anterior position.

It therefore seems clear that there are several types of pelvis among large groundbirds, depend-ing on their style of locomotion: cursorial taxa have a narrow pelvis, whereas more heavilybuilt forms, which presumably were not very fast runners, have a broader pelvis. Gargantuavisphiloinos clearly belongs to the second group. This, incidentally, probably indicates that it was notas functionally similar to ornithomimid “ostrich-dinosaurs” as originally suggested by Buffetautand Le Loeuff (1998), because ornithomimids had a rather narrow pelvis (Osmólska et al., 1972).

Among Cretaceous birds, Gargantuavis philoinos, which is probably not an ornithurine(Buffetaut and Le Loeuff, 1998), shows some resemblance with another flightless form,Patagopteryx deferrariisi, from Patagonia (Alvarenga and Bonaparte, 1992; Chiappe, 2002).Similarities include a broad pelvis, with ilia which do not meet above the synsacrum, and ananteriorly placed acetabulum (at the level of the 3rd and 4th synsacral vertebrae). Although thehen-sized Patagopteryx was much smaller than the ostrich-sized Gargantuavis, similarities inpelvis construction suggest that the condition seen in the giant French bird was not unusual forCretaceous flightless birds, although it differs in various respects from that of large Cenozoicgroundbirds.



4. On the rarity of Gargantuavis

Three bones only of this giant bird have been unearthed so far from three different localitiesof Late Campanian-Early Maastrichtian age. The holotype was found at the rich Bellevue quarry(Campagne-sur-Aude) in the south of the department of Aude and remains so far the only bird bonerecognized among more that 4000 vertebrate remains. Another partial synsacrum was found atBastide Neuve (Fox-Amphoux) in the department of Var where several hundred bones are known,including a second bird bone referred by Buffetaut et al. (2000) to the Enantiornithes. The femurwas discovered at Combebelle (Villespassans) in the department of Hérault where only a relativelysmall number of other bones, belonging mainly to dinosaurs, were found but the nearby locality ofMassecaps has yielded more than 4000 bones without a single Gargantuavis element. As a resultof the excavations led by different teams in Southern France and Spain in the last 20 years, tensof thousand of bones are now known from what is sometimes called the Ibero-Armorican Islandwhere Gargantuavis lived. Even if it is not unlikely that some yet unrecognized Gargantuavisbones have been discovered, it seems that this animal was remarkably rare in the Late Cretaceousecosystems of south-western Europe. Indeed it is even rarer than the few theropod taxa knownfrom the Ibero-Armorican Island, which may be a clue for a carnivorous diet as meat-eatingendothermic animals are usually much rarer than their herbivorous counterparts. Admittedly analternative explanation for this rarity may be linked to a different habitat with a lower chance offossilisation.

5. Conclusion

Comparisons between the pelvis and femur of Gargantuavis philoinos and those of variouspterosaurs, including azhdarchids, reveal very significant differences, which clearly show thatGargantuavis cannot be a pterosaur. The great width of its pelvis does distinguish it from cur-sorial groundbirds such as most present-day ratites or the extinct phorusrhacids, which possessa narrow pelvis. However, various heavily built groundbirds, such as many moas, gastornithidsand dromornithids, had a wide pelvis, like Gargantuavis. Not unexpectedly, Gargantuavis seemsto be closest morphologically to another Cretaceous flightless bird, Patagopteryx. Although it isstill very incompletely known, there is nothing to suggest that Gargantuavis was not a bird.

Acknowledgments

This work was supported by a grant from the INTERRVIE programme of the Institut desSciences de l’Univers, Centre National de la Recherche Scientifique. We thank Romain Vullo forhis constructive comments.

References

Alvarenga, H.M.F., Bonaparte, J.F., 1992. A new flightless landbird from the Cretaceous of Patagonia. In: Science Series,36. Natural History Museum of Los Angeles County, pp. 51–64.

Andrews, C.W., 1899. On the extinct birds of Patagonia. - I. The skull and skeleton of Phororhacos inflatus Ameghino.Transactions of the Zoological Society of London 15, 55–86.

Averianov, A.O., 2007. New records of azhdarchids (Pterosauria, Azhdarchidae) from the Late Cretaceous of Russia,Kazakhstan, and Central Asia. Paleontological Journal 41, 73–79.

Averianov, A.O., 2010. The osteology of Azhdarcho lancicollis Nessov, 1984 (Pterosauria, Azhdarchidae) from the LateCretaceous of Uzbekistan. Proceedings of the Zoological Institute of the Russian Academy of Sciences 314, 264–317.



Bennett, S.C., 2001. The osteology and functional morphology of the Late Cretaceous pterosaur Pteranodon. Part I.General description of osteology. Palaeontographica Abteilung A 260, 1–112.

Blanco, R.E., Jones, W.W., 2005. Terror birds on the run: a mechanical model to estimate its maximum running speed.Proceedings of the Royal Society B 272, 1769–1773.

Buffetaut, E., 1998. Ptérosaures et oiseaux du Crétacé supérieur de l’Aude. Bulletin de la Société d’Études Scientifiquesde l’Aude 98, 11–17.

Buffetaut, E., 2008. Late Cretaceous pterosaurs from France: a review. Zitteliana B28, 349–355.Buffetaut, E., Grigorescu, D., Csiki, Z., 2003. Giant azhdarchid pterosaurs from the terminal Cretaceous of Transylvania.

Special Publications, 217. Geological Society, London, p. 91–104.Buffetaut, E., Laurent, Y., Le Loeuff, J., Bilotte, M., 1997. A terminal Cretaceous giant pterosaur from the French Pyrenees.

Geological Magazine 134, 553–556.Buffetaut, E., Le Loeuff, J., 1998. A new giant ground bird from the Upper Cretaceous of Southern France. Journal of the

Geological Society, London 155, 1–4.Buffetaut, E., Le Loeuff, J., Mechin, P., Mechin-Salessy, A., 1995. A large French Cretaceous bird. Nature 377, 110.Buffetaut, E., Mechin, P., Mechin-Salessy, A., 2000. An archaic bird (Enanthiornithes) from the Upper Cretaceous of

Provence (Southern France). Comptes Rendus de l’Académie des Sciences 331, 557–561.Buffetaut, E., Mechin, P., Mechin-Salessy, A., 2006. An azhdarchid pterosaur from the Upper Cretaceous of Provence

(Southern France). In: Csiki, Z. (Ed.), Mesozoic and Cenozoic Vertebrates and Paleoenvironments. Tributes to theCareer of Professor Dan Grigorescu. Ars Docendi, Bucuresti, p. 95–100.

Cai, Z., Wei, F., 1994. On a new pterosaur (Zhejiangopterus linhaiensis gen. et sp. nov.) from Upper Cretaceous in Linhai,Zhejiang, China. Vertebrata Palasiatica 32, 181–194.

Chiappe, L.M., 2002. Osteology of the flightless Patagopteryx deferrariisi from the Late Cretaceous of Patagonia(Argentina). In: Chiappe, L.M., Witmer, L.M. (Eds.), Mesozoic birds. University of California Press, Berkeley, pp.281–316.

Donaire, M., López-Martínez, N., 2009. Porosity of Late Paleocene Ornitholithus eggshells (Tremp Fm, southcentralPyrenees, Spain): Palaeoclimatic implications. Palaeogeography, Palaeoclimatology, Palaeoecology 279, 147–159.

Eaton, G.F., 1910. Osteology of Pteranodon. Memoirs of the Connecticut Academy of Arts and Sciences 2, 1–38.Feduccia, A., 1999. The origin and evolution of birds. Yale University Press, New Haven & London, 466 pp.Fischer, K., 1962. Der Riesenlaufvogel Diatryma aus der eozänen Braunkohle des Geiseltales. Hallesches Jahrbuch für

mitteldeutsche Erdgeschichte 4, 26–33.Frey, E., Buchy, M.C., Stinnesbeck, W., González González, A., di Stefano, A., 2006. Muzquizopteryx coahuilensis n.g.,

n. sp., a nyctosaurid pterosaur with soft tissue preservation from the Coniacian (Late Cretaceous) of northeast Mexico(Coahuila). Oryctos 6, 19–40.

Lambrecht, K., 1933. Handbuch der Paläornithologie. Gebrüder Borntraeger, Berlin, 1024 pp.Matthew, W.D., Granger, W., 1917. The skeleton of Diatryma, a gigantic bird from the Lower Eocene of Wyoming.

Bulletin of the American Museum of Natural History 37, 307–326.Mayr, G., 2009. Palaeogene fossil birds. Springer, Berlin, 262 pp.Murray, P.F., Vickers-Rich, P., 2004. Magnificent Mihirungs. Indiana University Press, Bloomington & Indianapolis, 411

pp.Osmólska, H., Roniewicz, E., Barsbold, R., 1972. A new dinosaur, Gallimimus bullatus n. gen., n. sp. (Ornithomimidae)

from the Upper Cretaceous of Mongolia. Palaeontologia Polonica 27, 103–143.Paul, G., 2002. Dinosaurs of the air. Johns Hopkins University Press, Baltimore & London, 460 p.Sarjeant, W.A.S., Currie, P.J., 2001. The “Great Extinction” that never happened: the demise of the dinosaurs considered.

Canadian Journal of Earth Sciences 38, 239–247.Unwin, D.M., Lü, J., 1997. On Zhejiangopterus and the relationships of pterodactyloid pterosaurs. Historical Biology 12,

199–210.Wellnhofer, P., 1978. Pterosauria. Handbuch der Paläoherpetologie, 16. Gustav Fischer Verlag, Stuttgart, 82 p.

gargantuavis philoinos: giant bird or giant pterosaur?

Documents