Cerquiera et al. 2021 reported,
“Mechanical preparation revealed that the original concretion bearing the fossil was a composite, in which the rostral ends of the premaxillae and dentaries of a second pterosaur specimen was glued to the holotype. In order to avoid misinterpretations, we choose to only illustrate those elements that safely belong to a single individual. The exact location where MPSC R 1056 was found is, unknown, since the specimen was donated to MPSC by local workers.”
I wonder if this was before or after the threat of arrest?
Apparently the local workers wanted to sell this specimen on their own and attempted to make it look more marketable before ‘realizing the error of their ways’ and ‘donating’ their poorly prepared specimen to the MPSC (Museu de Paleontologia Plácido Cidade Nuvens, Santana do Cariri, Brazil). If their intentions were honorable, as soon as the local workers found the specimen they would have asked their boss to find a museum paleontologist pronto!
You find this sort of thing
wherever there is a market for pterosaur skeletons and skulls.
The authors reported
MPSC R 1056 as a 2-part chimaera (Fig. 1), but illustrated it as a 3-part chimaera. They gave the small (Fig. 2) specimen a name: Kariridraco dianae based on what appears to be glued together AND taphonomically damaged and scattered specimen.
Given that part of the specimen is recognized as chicanery,
should musuem specialists be giving the rest of this specimen their ‘blessing’ based on what is apparently more chicanery and/or overlooked taphonomic scattering?
The authors report,
“The unusually steep premaxillary crest and the fact that the rostrum anterior to this structure was adulterated by fossil dealers led us to raise concerns about the crest authenticity. Careful examination of the fossil and surrounding matrix revealed that, although there are signs of a breakage close to the base of the crest (where it contacts the main body of the premaxillomaxilla), the two resulting counterparts fit together, with no signs of add-ons or other modifications. Bone surface at the base of the crest was eroded off, so that trabecular bone is exposed at that portion.”
If the mid-portion of the specimen had normal proportions,
it would be more acceptable. But it doesn’t have typical, traditional proportions. That’s a red flag. That signals more chicanery. The crest base is not firmly attached to the jaws, as recognized by the authors. The unusually high crest angle is the result of taphonomic damage mistakenly accepted as a real trait. The matrix may be undisturbed because taphonomic shifting on a broken up fossil is not the same as preparator chicanery. This is why you have to be on the lookout for both and a reconstruction is so important before scoring traits.
The bone break that is most interesting
is the one close to the anterior of the antorbital fenestra. This is the one that greatly shortens the skull (Figs. 1a, 1b). When separated to normal proportions based on the underlying blueprint all the bones are still the correct size for a juvenile tupuxuarid (Fig. 2).
The authors did not mention the small overall size of the specimen.
Nor did the term ‘juvenile’ enter the text. Nor did they mention the Goshura (Japan) specimen. The complete, 3D juvenile tupuxuarid serving as the blueprint (Fig. 1) may not be in a museum. I saw it at a fossil expo in Arizona several decades ago.
The pterosaur cladogram provided by Cerqueira et al. was borrowed,
and borrowed and borrowed again. Outgroup taxa include three very un-pterosaurian taxa and the basal pterosaur is a highly derived anurognathid. Embarrassing to see this as professional output. We’ve known more parsimonious pterosaur outgroup taxa for twenty years. We’ve had more complete pterosaur cladograms for a decade or more.
The lessons for today,
1. Be wary of composite (some call these ‘fake’) fossils. 2. Try to describe new genera on the basis of better preserved specimens. 3. Create reconstructions and compare them to known, more complete taxa. 4. No need to include Scleromochlus and other archosauriforms in a pterosaur cladogram that focuses on tapejards and tupuxuarids. A series of Germanodactylus and dsungaripterids will do.
Some specimens just belong in the back, on the shelves,
until someone is willing to put in the effort required to understand the chicanery and taphonomy by creating a reconstruction that can be properly scored using the tools of comparative anatomy.
Cerqueira GM, Santos MA, Marks MF, Sayão JM and Pinheiro FL 2021. A new azhdarchoid pterosaur from the Lower Cretaceous of Brazil and the paleobiogeography of the Tapejaridae. Acta Palaeontologica Polonica. 66. doi:10.4202/app.00848.2020