Upper Cretaceous localities in Egypt are well-known for
yielding the genoholotypic specimens of a number of
distinctive non-avian dinosaurs, such as
Carcharodontosaurus, Paralititan, Mansourasaurus, and,
most famously, Spinosaurus; nevertheless, material of
other ornithodiran archosaurs has remained elusive. Here
we report an isolated, three-dimensionally preserved left
first wing phalanx (left manual phalanx IV-1) of a
medium-sized pterosaur from an amalgamated braidedchannel-fill deposit of the lower Cenomanian Bahariya
Formation of the Bahariya Oasis, Western Desert of
Egypt. The specimen represents the first pterosaur record
from Egypt, and it compares favorably with the
equivalent element in pteranodontian (sensu stricto; i.e.,
pteranodontid and nyctosaurid) pterosaurs, rather than
ornithocheiromorphs or azhdarchoids. The fused and
ossified extensor tendon process (ETP) indicates that the
individual in question was osteologically mature. The
proximal ETP of the specimen is comparable in overall
morphology to that of Pteranodontia in features such as
the subrectangular extensor tubercle, the position of the
prominent pneumatic and the small nutrient foramina, the
expanded curvature of the dorsal cotyle, the thin bony
wall, and the posterior flare of the proximal articulation.
Moreover, the specimen differs morphologically from the
first wing phalanx of penecontemporaneous azhdarchoids,
which typically possess a subtriangular extensor tubercle
and weaker curvature of the dorsal cotyle. The presence
of a pteranodontian in the lower Cenomanian Bahariya
Formation represents one of the earliest known
occurrences of the clade and adds to mounting evidence
of high taxonomic diversity of the group in the Upper
Cretaceous of North Africa.
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