Gegepterus changi
Several elements including unfused cranial bones and scapula-coracoid
Abstract: A partial skeleton
(including skull, mandible and soft tissue) of a new archaeopterodactyloid
pterosaur, Gegepterus changi gen. et sp. nov. from the Lower Cretaceous
of Liaoning, northeast China is described. The specimen, IVPP V 11981, was
collected from grey shales of the lower Yixian Formation (125 Ma) at the
Sihetun locality, near the city of Beipiao. Several elements (cranial bones,
scapula-coracoid) are not fused, suggesting that it probably represents a
sub-adult individual at the time of death. Soft tissue is found near the
posterior region of the skull, inside the orbit and associated with the
gastralia. It is formed of an amorphous dark mineralized substance and does
not show any particular structure except in an area at the posterior part of
the skull where small, dark, unbranched fibres are present. Gegepterus
changi shows synapomorphies of the Archaeopterodactyloidea sensu Kellner,
2003 (elongated mid-cervical vertebrae with low, blade-like neural spine and
strongly inclined quadrate) and shares with the Gallodactylidae and the
Ctenochasmatidae a concave dorsal margin of the skull. It further has a large
number of thin, needle-like teeth and a long rostrum (anterior to the
nasoantorbital fenestra) allowing its allocation to the Ctenochasmatidae, thus
making it the first uncontroversial member of this pterosaur clade in the
Jehol Group. Gegepterus changi is diagnosed by several unique features
(e.g., extensive sculpturing of frontals; anterior lacrimal process overlying
the nasal; neural spine with knob-like dorsal expansion) and has cervical
vertebrae that combine primitive and derived features (e.g., cervical ribs,
postexapophyses, lateral pneumatic foramen) that have not been recorded in any
member of Archaeopterodactyloidea so far.
Keywords: Pterosauria; Archaeopterodactyloidea;
Ctenochasmatidae; Liaoning; Early Cretaceous; China