Yesterday we looked at the adult sisters to the JZMP embryo. Today we’ll do the same with the IVPP embryo.
Figure 1. Large anurognathids and their typical-sized sisters. Here the IVPP embryo enlarged to adult size is larger than D. weintraubi and both are much larger than more typical basal anurognathids, Mesadactylus and MCSNB 8950.
The IVPP embryo pterosaur (Wang et al. 2004), the first ever described, was wrongly considered a juvenile ornithocheirid based on its small tail and short rostrum. At the time pterosaur juveniles were purported to have a short rostrum, but this has been proven wrong at every turn. First on that list: the JZMP embryo is an ornithocheirid and it has a long rostrum.
Phylogenetic analysis nests the IVPP embryo pterosaur together with Mesadactylus, a poorly known anurognathid. Both are sister to another large anurognathid, the misnamed “Dimorphodon” weintraubi. And all three were derived from a sister to MCSNB 8950, wrongly considered a juvenile “Eudimorphodon.”
It’s a wonder to see a giant anurognathoid with an embryo the size of other anurognathoids. Only D. weintraubi approaches the embryo enlarged to adult size. Can’t wait for someone in China to come out with the big news of the discovery of the adult.
References
Wang X-L and Zhou Z 2004. Palaeontology: pterosaur embryo from the Early Cretaceous. Nature 429: 623.
The Pterosaur Heresies 