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| Hypothetical reconstruction of Oxfordian rhamphorhinchids: MUHNCAL.20165 (Rhamphorhynchinae gen. et sp. indet.), Cerro Campamento Formation, Chile in Alarcón-Muñoz, Otero, Soto-Acuña, ... et Rojas, 2021. Artwork: facebook.com: Mauricio Alvarez |
We describe partial remains of a non-pterodactyloid pterosaur from Upper Jurassic levels of the Atacama Desert in northern Chile. The material includes a left humerus, a possible dorsal vertebra, and the shaft of a wing phalanx, all preserved in three dimensions and likely belonging to a single individual. The humerus has a hatchet-shaped deltopectoral crest, proximally positioned, and its shaft is markedly anteriorly curved, which are characteristic features of the clade Rhamphorhynchidae. In addition, the presence of a groove that runs along the caudal surface of the phalanx, being flanked by two asymmetric crests, is a distinctive feature of the clade Rhamphorhynchinae, which includes such genera as Rhamphorhynchus and Nesodactylus. Previous to this research, known records of Rhamphorhynchinae were restricted to Laurasia; thus, the specimen studied here represents the first evidence of this group found to date in Gondwana. Associated ammonoids allow us to assign the material to a middle Oxfordian age, which makes this specimen the oldest known pterosaur found in Chile, and the first of Oxfordian age in Gondwana. This discovery suggests that the clade Rhamphorhynchidae had a global distribution during the Late Jurassic.
Key words: Pterosauria, Rhamphorhynchidae, Rhamphorhynchinae, Oxfordian, Chile, Laurasia, Gondwana.
Systematic palaeontology
Diapsida Osborn, 1903
Archosauria Cope, 1869
Pterosauria Kaup, 1834
Breviquartossa Unwin, 2003
Rhamphorhynchidae Seeley, 1870
Rhamphorhynchinae Nopcsa, 1928
Rhamphorhynchinae gen. et sp. indet.
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| Fig. 3. Rhamphorhynchinae gen. et sp. indet. (MUHNCAL.20165) from Cerritos Bayos, west Calama, Chile; Cerro Campamento Formation, middle Oxfordian. Left humerus in dorsal (A1 , A5), posterodorsal (A2 , A6), posterior (A3 , A7), and ventral (A4 , A8) views, photographs (A1 -A4) and explanatory drawings (A5 -A8). |
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| Fig. 7. Simplified map of the world during the Oxfordian. The dashed line represents the hypothetical route that would have allowed the dispersal of marine vertebrates and invertebrates between Tethys and South America during the Late Jurassic (Caribbean corridor). The finds of Oxfordian rhamphorhinchids: MUHNCAL.20165 (Rhamphorhynchinae gen. et sp. indet.), Cerro Campamento Formation, Chile (circle); Cacibupteryx caribensis (Gasparini et al. 2004) and Nesodactylus hesperius (Colbert et al. 1969), Jagua Formation, Cuba (square); Rhamphorhynchinae gen. et sp. indet. (Lydekker 1890, O'Sullivan 2018), Oxford Clay Formation, UK (star); Qinglongopterus guoi (Lü et al. 2012), Tiaojishan Formation, China (triangle). Modified map from Scotese (2014). |
Jhonatan Alarcón-Muñoz, Rodrigo A. Otero, Sergio Soto-Acuña, Alexander O. Vargas, Jennyfer Rojas, and Osvaldo Rojas. 2021. First Record of A Late Jurassic Rhamphorhynchine Pterosaur from Gondwana. Acta Palaeontologica Polonica. in press. DOI: 10.4202/app.00805.2020
Investigadores U. de Chile identifican enigmático "dragón volador" del Jurásico por primera vez en el Hemisferio Sur
MUHNCAL, Museo de
Historia Natural y Cultural del Desierto de Atacama,
Calama, Antofagasta Region, Northern Chile
