Monday, July 23, 2012

[Paleontology • 2011] Aurorazhdarcho primordius • The oldest azhdarchoid pterosaur from the Late Jurassic Solnhofen Limestone (Early Tithonian) of Southern Germany

Aurorazhdarcho primordius n.gen. n.sp., holotype (NMB Sh 110)

Based on an almost complete three-dimensionally preserved skeleton, a new genus and species of an azhdarchoid pterosaur Aurorazhdarcho primordius n.gen. n.sp. from the Late Jurassic Solnhofen limestone (Early Tithonian) of the Eichsta¨tt area (Bavaria, Germany) is described. Furthermore, a new family the Protazhdarchidae is proposed. The specimen is attributed to the Azhdarchoidea based on its glenoid fossa level with the sternum, the shovel-like shape of the sternal plate, the wide furca of the coracoid, the metacarpus being longer than radius and ulna, the femur being 1/3 longer than the humerus, the femorotibial ratio, and the hammer-shaped humerus among other diagnostic features. Under UV-light, soft tissue preservation around the external mould of the head is visible. It consists of tiny flakes possibly remnants of skin. The dorsally curved outline of the external mould of the head suggests the presence of a cranial crest. The new species is the oldest record of the azhdarchoid pterosaurs. It supports the Eurasian origin of this group that includes the largest flying animal ever.
Keywords: Azhdarchoidea, Pterosauria, Soft tissue preservation, Tithonian, Southern Germany

Reconstruction of Aurorazhdarcho primordius n.gen. n.sp in ventral aspect. The asterisks indicate the body parts that are reconstructed from the soft tissue patch and the external moulds

Systematic palaeontology
Pterosauria KAUP 1834
Azhdarchoidea UNWIN 1995

Protazhdarchidae nov. fam.
Aurorazhdarcho n.gen.
Aurorazhdarcho primordius n.sp.

Derivatio nominis: Genus name from Latin aurora = dawn and Kirgisian azhdarcho = dragon; species name from Latin primordius = the earliest

Holotypus: A single articulated skull- and neckless specimen housed in the Natural History Museum Basel
(Switzerland) under the collection number NMB Sh 110 (Figs. 2, 3)

Locus typicus: Blumenberg Quarry near Eichsta¨tt (Bavaria, Germany; Fig. 1) 

Stratum typicum: Solnhofen Lithographic Limestone (Upper Eichsta¨tt Formation, Late Jurassic, Lower Tithonian, Hybonotum Zone; Schweigert 2007).

Fig. 3 Aurorazhdarcho primordius n.gen. n.sp., holotype (NMB Sh 110).a. Under UV light with luminescent soft tissue traces;b. line drawing of the skeleton and the soft tissue preservation as seen under UV-light. Scale bar 50 mm

Eberhard Frey, Christian A. Meyer and Helmut Tischlinger. 2011. The oldest azhdarchoid pterosaur from the Late Jurassic Solnhofen Limestone (Early Tithonian) of Southern Germany. Swiss Journal of Geosciences. 104 (Supplement 1): 35–55. 
the issue entitled "Proceedings of the 5th International Symposium on Lithographic Limestone and Plattenkalk"