Ornithischian scapulae

[Richard Butler <rbut02@esc.cam.ac.uk>]

If anyone fancies being dragged away from theropods for a while....

One of the synapomorphies used to support Eurypoda (ankylosaurs and
stegosaurs) by Galton (1990) and Sereno (1999) is a parallel-sided scapula
blade as opposed to the basal condition in which it is distally expanded.
However those stegosaurs for which I have pictures (Stegosaurus,
Huayangosaurus, Chungkingosaurus) appear to have distally expanded blades,
whereas ankylosaurs do seem to have parallel-sided blades. Parallel (or near
parallel) sided blades are also seen in some ornithopods such as Iguanodon
and Probactrosaurus.

Do basal stegosaurs actually show a parallel-sided scapula blade? Do people
consider that the character is actually a valid synapomorphy of Eurypoda?
Any help would be much appreciated.

Richard Butler