IVPP embryo pterosaur (Wang and Zhou 2004, IVPP V13758) Early Cretaceous, ~125 mya was previously considered a juvenile ornithocheirid based on the size of the embryo, the presence of a short tail and the false hypothesis that pterosaurs matured allometrically and were hatched with large eyes and a short rostrum. (Wellnhofer 1970, Bennett 1993a, b, 1995, 1996a, 2001a,b, 2006, 2007, Wang and Zhou 2004). While the IVPP embryo had a short rostrum that is because it was a protoanurognathid. A genuine ornithocheirid embryo, the JZMP embryo, had an elongated rostrum and small eyes. The Pterodaustro embryo had an even longer rostrum and smaller eye. The surprising data about this specimen is its size. The embryo is about the size of most adult anurognathids. Only one sisiter taxon was large enough to be its parent, the mislabeled Dimorphodon weintraubi. Derived from a sister to MCSNB 8950, the IVPP embryo phylogenetically preceded Dimorphodon weintraubi.

The skull is unknown in the three more primitive sister taxa. Distinct from Dimorphodon, the skull of the IVPP embryo had a smaller naris but was otherwise quite similar. The postorbital was larger. The dentary teeth were relatively larger.

The cervical neural spines were shorter. Approximately 10 vertebrae were sacrals. The caudals were reduced to a vestige.

The sternum was rectangular. The scapula was shorter. The coracoid ventral stem was not expanded. The humerus was half the relatrive length as in sister taxa and therefore may be a trait associated with immaturity, but that is speculation awaiting further data. The metacarpus was longer than in sister taxa. Manual 4.4 was relatively shorter.

The pelvis was relatively larger. The ischium and pubis was notched and the ischium was broad. The hind limb and especially the tibia was longer. Pedal 5.1 did not extend to the tip of metatarsal IV.

The eggshell was thinner than in any archosaur or archosauromorph (Deeming and Unwin 2007) and most like that of lizards that retain the embryo until just before hatching. It would be ridiculous to expect tiny to extremely tiny hatchling pterosaurs to crawl through sand or mud after being buried prior to hatching, as Deeming and Unwin (2007) and Grellet-Tinner et al. (2007) proposed under the false archosaur paradigm (Bennett 1996b). They were not as tough as little turtles and crocs.

This taxon is only known from an embryo just days or minutes prior to hatching. We know that it greatly resembled the adult and matured isometrically due to the examples of other clade members, Huehuecuetzpalli (Reynoso 1998), the JZMP embryo (Ji et al. 2004), the Pterodaustro embryo, (Chiappe et al. 2004) and the Pteranodon ingens juvenile. This upsets a long-standing tradition (Wellnhofer 1970, Bennett 1993a, b, 1995, 1996a, 2001a,b, 2006, 2007, Wang and Zhou 2004) that pterosaurs mature allometrically like birds, crocs and mammals.

Additional data from the embryo fossil were identified by following the universally criticized methods described here. This is evidence that photo interpretation can be superior to first-hand observation, principally due to digital graphic segregation and persistence.

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