Fernando E. Novas, Martin Kundrat, Federico L. Agnolín,  Martín D. Ezcurra, Per Erik Ahlberg, Marcelo P. Isasi,  Alberto Arriagada, y Pablo Chafrat

Here, we expand the meager record of Late Cretaceous South American pterosaurs with the description of a partial rostrum belonging to a large azhdarchid pterodactyloid. The specimen was collected close to the Bajo de Arriagada locality, corresponding to the uppermost Cretaceous Allen Formation of Argentina, around 80 km northwest of the well-sampled Bajo de Santa Rosa locality (Martinelli and Forasiepi, 2004). The Azhdarchidae were the most abundant pterosaurs during latest Cretaceous times (Company et al., 1999; Butler et al., 2009). This clade comprises several species of long-necked pterosaurs ranging from 2.5 to 10 m in wing span, thus including the largest known flying vertebrates, such as the gigantic Quetzalcoatlus and Hatzegopteryx (Kellner and Langston, 1996; Buffetaut et al., 2002; Witton and Naish, 2008; Witton and Habib, 2010). Azhdarchid remains have been documented from almost all continental landmasses, includ-ing Europe, North America, Africa, Asia, and probably Oceania (Bennett and Long, 1991; Company et al., 1999; Averianov et al., 2005; Barrett et al., 2008; Kear et al., 2010; ˝Osi et al., 2011). In South America, probable azhdarchid remains consist of a fragmentary postcranial skeleton from the Aptian of Brazil (Martill and Frey, 1998, 1999) and partial long bones from the Turonian–Coniacian of Argentina (Kellner et al., 2006; Codorniú and Gasparini, 2007). However, recent reassessments of this material suggested that the Brazilian specimen is more closely related to tapejarids than to azhdarchids and that the Argentinean records are dubious (Kellner, 2004; Kellner et al., 2006; Unwin and Martill, 2007). As a result, the specimen reported here represents the first unambiguous evidence of an azhdarchid pterosaur from South America. This specimen represents a new genus and species, Aerotitan sudamericanus, which is diagnosed based on a unique combination of characters, including one autapomorphy, and represents one of the largest known South American pterosaurs. The fossil here described resulted from a joint Argentine-Swedish paleontological expedition to Patagonia.

Novas, F. E., Kundrat, M., Agnolín, F. L., Ezcurra, M. D., Ahlberg, P. E., Isasi, M. P., Arriagada, A. y Chafrat, P. 2012. A New Large Pterosaur From The Late Cretaceous Of Patagonia. Journal of Vertebrate Paleontology 32(6):1447–1452