The Late Jurassic Pterosaurs from Northern Patagonia, Argentina

Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 103, 1–10, 2013 (for 2012) The Late Jurassic pterosaurs from northern Patagonia, Argentina Laura Codorniu´ 1 and Zulma Gasparini2 1 CONICET, Departamento de Geologıá, Universidad Nacional de San Luis, Chacabuco 917, 5700 San Luis, Argentina. Email: [email protected] 2 CONICET, Divisioń Paleontologıá de Vertebrados, Museo de La Plata, 1900 La Plata, Argentina. Email: [email protected] ABSTRACT: Records of flying Jurassic reptiles are very scarce in the Southern Hemisphere. Upper Jurassic pterosaurs have been discovered in marine Tithonian sediments of the Vaca Muerta Forma- tion, in the Neuqueń Basin, Patagonia, Argentina. Only four specimens are known so far: the first from Arroyo PicuńLeufu´, and the other three from the lithographic limestones of Los Catutos. Here, we update knowledge of Late Jurassic pterosaurs from northwest Patagonia. We revise the diagnosis and description of a previously described pterodactyloid, which is named as a new genus and species, Wenupteryx uzi. This small-sized pterosaur shows affinities with Euctenochasmatia or Archaeoptero- dactyloidea, and represents the most complete Jurassic pterosaur so far known from the Southern Hemisphere. We also report a recent finding suggesting that the new specimen belongs to a new species of pterodactyloid pterosaur. These records show that at least three different taxa of pterosaurs co- existed in the Neuqueń Basin: Herbstosaurus, Wenupteryx and a more derived pterodactyloid that represents the largest pterosaur known from the Upper Jurassic of Gondwana. KEY WORDS: Northwest Patagonia, Pterodactyloidea, systematics, Tithonian, Upper Jurassic. During the Jurassic, there was a broad tropical belt and the recently described Darwinopterus (Lu¨ et al. 2010) at the base polar regions were only slightly cooler, so the Earth’s climate of the Pterodactyloidea (Codorniu´ et al. 2010). was warmer and more equable than that of today (Hallam Fragmentary remains are known from the finely laminated 1993). At that time, pterosaurs had a worldwide distribution limestones of different localities from the Kota Formation of (Wellnhofer 1991; Unwin 1996). However, their known record Kota, India (Rao & Shah 1963). This Formation was previously is markedly biased toward the northern hemisphere. For ex- assigned to the Early Jurassic based on semionotid (Jain 1973) ample, numerous Jurassic fossil-bearing deposits have yielded and pholidophorid fishes (Yadagiri & Prasad 1977), but now it a large variety of specimens representing basal and derived taxa is regarded as late Middle Jurassic to possibly Early Cretaceous in Europe (e.g. Wellnhofer 1978, 1991; Padian & Wild 1992; (Prasad & Manhas 2007). These fossils are isolated, incomplete Unwin 1996), in North America (Galton 1981; Padian 1984; fragments assigned to ‘‘Campylognathoides indicus’’ (Jain 1974) King et al. 2006; Bennett 2007), in the Caribbean (Colbert and consist of the anterior part of the skull and upper jaw, and 1969; Gasparini et al. 2004) and in China, from the Tiaojishan a few incomplete post-cranial bones. However, the assignment Formation (e.g. Lu¨ et al. 2010, 2011; Wang et al. 2010; Cheng of the type specimen of ‘‘C. indicus’’ has been questioned by et al. 2012). Padian (2008a), who suggested that the jaw most likely belongs In contrast, Jurassic pterosaurs are extremely rare in the to a fish. The post-cranial bones merit re-study, given that they southern hemisphere (Fig. 1). The oldest record in Gondwana have no real affinity to Campylognathoides, and it is possible comes from the Middle Jurassic of Patagonia, in the Canãdoń that this material represents a new taxon (Padian 2008a). Asfalto Formation, which is mainly composed of lacustrine Late Jurassic Gondwanan pterosaurs are known from Africa deposits and has provided the most diverse vertebrate fauna and Patagonia (Fig. 1). Most pterosaur remains from Africa known from the early Middle Jurassic in the southern hemi- have been recovered from the Upper Saurian bed and the sphere. New data indicate that the lacustrine levels of the Transitional Sand at the base of the Upper Saurian bed Canãdoń Asfalto Formation in the vicinity of the village of (Kimmeridgian to Tithonian) from Tendaguru, Tanzania (Reck Cerro Cońdor probably range from the uppermost Toarcian 1931; Galton 1980). Unwin & Heinrich (1999) re-examined these to the lowermost Bathonian (Cabaleri et al. 2010; Cuńeo & specimens and concluded that all previously named pterosaur Bowring 2010). Pterosaur remains have been discovered in taxa from Tendaguru (‘Rhamphorhynchus tendagurensis’, ‘Pter- several localities where this unit is exposed and were briefly odactylus maximus’, ‘Pterodactylus brancai’ and ‘Pterodactylus reported by Rauhut et al. (2001) and Unwin et al. (2004). Fur- arnigi’) should be considered nomina dubia. They also claimed ther information on these remains was reported by Codorniu´ that this African sample comprised two pterosaurs, a ‘rham- et al. (2010) and the material is currently under study. The phorynchoid’ and (following Galton 1980) a dsungaripteroid osteological features indicate that this assemblage contains pterodactyloid. They named the latter taxon Tendaguripterus subadult and juvenile individuals. Their wingspan was calcu- recki (Unwin & Heinrich 1999), based on an incomplete short lated on the basis of wing phalanges and was estimated at section of the small mandibular symphysis. Recently, new approximately 1 m for the subadult specimens. Preliminary material from Tendaguru has been described (Costa & Kellner phylogenetic analysis places the taxon in a polytomy with the 2009): a proximal portion of a right humerus assigned to the 6 2013 The Royal Society of Edinburgh. doi:10.1017/S1755691013000388 2 LAURA CODORNIU´ AND ZULMA GASPARINI Figure 1 Distribution of Jurassic pterosaurs in the Southern Hemisphere (modified from Unwin, 2006). The star-shaped dots represent records of Jurassic pterosaurs in Gondwana. Figure 2 (A) Palaeogeography of the Neuqueń Basin seas; (B) locality map of the area of Los Catutos and Arroyo Picuń Leufu´, Neuqueń Province. Dsungaripteroidea and a complete, and very small humerus re- from Los Catutos (Fig. 2), Los Catutos Member, Vaca Muerta ferred to the Archaeopterodactyloidea (Costa & Kellner 2009). Formation, referred to the Late-Middle Tithonian (Leanza & Like most marine reptiles found in the Neuqueń Basin, Zeiss 1990, 1992). The first of these pterosaur specimens was northern Patagonia (Fig. 2), pterosaurs have been discovered an isolated limb bone of a small pterodactyloid discovered in in marine deposits of the Vaca Muerta Formation. This unit the 1980s (Gasparini et al. 1987). Twenty years later, an articu- represents a short transgressive episode that is biostratigra- lated skeleton was described and is the most complete ptero- phically constrained to the Tithonian–Valanginian. It entered saur known from the Upper Jurassic of Gondwana (Codorniu´ from the Pacific Ocean and covered a large part of the basin et al. 2006). Recently, a slab of lithographic limestone was (Spalletti et al. 2000). Among the four specimens found in the found in Zapala city (Neuqueń Province). It contained an Vaca Muerta Formation, the first discovered was the ptero- intact impression of an isolated bone, which we identify here dactyloid Herbstosaurus pigmaeus Casamiquela, 1975 from as a pterosaur tibiotarsus, larger than those so far known in Arroyo Picuń Leufu´ and National Route 40, in Upper Titho- the area (Codorniu´ & Garrido, submitted). These specimens nian rocks (Codorniu´ & Gasparini 2007, fig. 6.7). The other from the Neuqueń Basin are the only records of Pterosauria three specimens were found in the lithographic limestones from the South American Upper Jurassic. LATE JURASSIC PTEROSAURS FROM PATAGONIA 3 Figure 3 Wenupteryx uzi, gen. et sp. nov., composite drawing of MOZ 3625P. Abbreviations: c ¼ carpals; cl ¼ claw; cor ¼ coracoid; cv ¼ cervical vertebrae; dt ¼ distal tarsals; dv ¼ dorsal vertebrae; fb ¼ very fragmentary bones; fe ¼ femur; g? ¼ aaa;hu¼ humerus; il ¼ ilium; isq ¼ isquion; (l) ¼ left; mcI? ¼ wing metacarpal I?; mc II/III? ¼ wing metacarpal II or III; mcIV ¼ wing metacarpal IV; mph ¼ manual phalanges; mt ¼ meta- tarsals; pph ¼ pedal phalanges; ppu ¼ prepubis; prcor ¼ procoracoid; pu ¼ pubis; pt ¼ pteroid; (r) ¼ right; ra ¼ radius; ri ¼ rib; sc ¼ scapula; ti ¼ tibia; ul ¼ ulna; wph 1–3 ¼ wing phalanges 1–3. In this chapter, in homage to Prof. Emeritus Dr. Wann Type species. Wenupteryx uzi, sp. nov. Langston Jr, we update the knowledge of Late Jurassic ptero- Etymology. In the Mapuche language, Wenu means ‘sky’ saurs from northern Patagonia: we describe a new taxon, and pteryx is the Greek word for ’wing’. The specific epithet based on the preparation and study of a specimen originally uzi means ‘fast’ in the Mapuche language. Mapuches are abo- described by Codorniu´ et al. (2006); we revise the taxonomic rigines from central Chile and central-western Argentina. placement of the single isolated bony element of the first pter- Diagnosis. Condyle of the mid-cervical vertebrae posteriorly odactyloid found in Los Catutos (Gasparini et al. 1987); and convex at its dorsal and ventral margins, with a concave depres- we report a new specimen that shows that not only small pter- sion at its midpoint; prepubis with asymmetric distal extension, osaurs flew over the Tithonian seas of the Neuqueń Basin. in which the lateral half is sub-rectangular and the medial

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