[N] 2006 The smallest pterosaur from the Early Cretaceous Jehol biota
Kellner, A., Campos, D., Wang, X. & Zhou, Z. (2006) The smallest pterosaur from the Early Cretaceous Jehol biota, China JVP 26(3) Abstracts pp.84
A new pterosaur from the Liaoning deposits, northeastern China is reported. The specimen (IVPP V-14377) consists of an almost complete skeleton that was collected in the Jiufotang Formation (~120 Ma), close to Jianchang, western part of Liaoning. The maximum length of the skull is 39.6 mm (sq-pm: 37.8 mm). The posterior region of the skull is expanded and the articulation with the mandible is positioned under the anterior half of the orbit. The orbit is sub-oval and comparatively large. The nasoantorbital fenestra is comparatively small, occupying about 25% of the sp-pm length.
The confluent naris and antorbital fenestra, the absence of ribs in the mid-cervicals, and the reduced fifth pedal digit indicates that IVPP V- 14377 is a member of the Pterodactyloidea. The new specimen further lacks any synapomorphy of the Archaeopterodactyloidea and the toothless condition suggests that it is a member of the Dsungaripteroidea. The humerus has a proximally placed and slightly curving deltopectoral crest, differing from the hatched-shaped or warped condition of, respectively, the Nyctosauridae and the Pteranodontoidea. The short mid-cervical vertebrae are distinct from the Azhdarchidae and the small size of the nasoantorbital fenestra from the Tapejaridae.
The absence of a premaxillary sagittal crest is another character that distinguishes it from all known clades of the Dsungaripteroidea. IVPP V-14377 further shows some unique features (e.g., high caudals, distinct medial process on femur, curved phalanx of first pedal digit) suggesting that it belongs to a new taxon, and expands the diversity of the Jehol pterosaur fauna. The estimated wingspan of IVPP V-14377 is around 20 cm, making it one of the smallest pterosaur ever found. Several bones are unfused (e.g., scapula and coracoid, cranial bones), but the tarsals are ossified, suggesting that it was a juvenile but probably not a hatchling.