Derived Ornithocheirids – Where are the prepubes??

All pterosaurs have a prepubis, right?
That’s that little addition to the pubis that only fenestrasaurs, including pterosaurs, have, convergent with marsupial bones in mammals. Oddly they are not often found in several ornithocheirids, which are not often found articulated.

Zhenyuanopterus is complete and articulated, but the prepubes, if present, would be beneath the crushed pelvis.

Where found, as in the basal ornithocheirids,m JZMP embryo, Boreopterus, Haopterus, Arthurdactylus and the large istiodactylid, SMNK PAL 1136, the prepubes are typically small with a slender stem and a broader ventral plate. We still haven’t found prepubes for  Anhanguera, Tropeognathus, Coloborhynchus, Brasileodactylus, Nurhachius or Istiodactylus (Fig. 1). Still looking.

Figure 1. The Ornithocheiridae. Click to enlarge and expand.