Ubirajara is an extinct genus of compsognathid that lived in Brazil during the Early Cretaceous.


Ubirajara is known from a single specimen, which preserves an array of hard-to-fossilize material such as feather, keratin, adipocere and epidermal structures. This genus has a large feather "mane" which starts midway down the dinosaurs back and covers the remainder of the body in a thick layer. Most dinosaurs that preserve vast arrays of feather and similar structures are usually maniraptoriformes and small ornithischians. Ubirajara represents the first non-avian theropod preserving filamentous integument.

Ubirajara is also the first non-maniraptor to possess elaborate structures likely used for display. In this animals range of integument include slender monofilaments at the base of the neck, which increase in length to the dorsal thoracic region forming a large "mane". Additionally, Ubirajara bears large ribbon-like filaments that likely sprout from the shoulder. Such structures are unknown in any dinosaur, until now. However, similar structures appear in the extant genus Semioptera. It has been suggested that said "mane" and filamentous structures in Ubirajara could have been pushed upwards/outwards by muscles during display season, This means that the base position would have the structures tucked into the body, and then shot out when needed.

History and Discovery

Ubirajara was originally discovered in Brazilian fossil mines, to which author David M. Martill bought and exported the specimen from South American museums. Brazilian fossil laws state that fossils are considered property of the state, which therefore makes selling and exporting illegal, and if it is exported, requires at least Brazilian researcher to work on the specimen. This researcher has used similar methods before, notably with an exquisitely-preserved Brazilian snake fossil holotype specimen; Tetrapodophis. Since publication, it has been argued that the specimen should be transported back to the museum the fossil was to be originally brought to and further studied by Brazilian paleontologists. In the past, when questioned about unethical fossil handling, the researcher has said this about Tetrapodophis and similar specimens:

[...] doesn't care a damn how the fossil came from Brazil! [...] But what difference would it make [about partnering with a Brazilian researcher]? I mean, do you want me also to have a black person on the team for ethnicity reasons, and a cripple and a woman, and maybe a homosexual too, just for a bit of all round balance?
—Martill (when asked about partnering with Brazilian scientists)

After that interview, he closed with a reference to Sir Richard Owen digging bodies from graveyards to study human anatomy during the 1800s, in an attempt to justify his actions. Since then, #UbirajaraBelongsToBR has trended on Twitter in an attempt to repatriate the fossil. Ubirajara is not the first fossil to be illegally smuggled from Brazil, as the case for several undescribed remains from museums.

Documents sent by Frey over Email.

However, researcher Eberhard "Dino" Frey has told may users Email that the holotype was exported legally, citing documents written in Portuguese. After further analysis, it is determined the documents appear to be genuine, and roughly state the following:

National Mineral Production Department (DNPM) of the Ministry of Mines and Energy (MME) through the Chapada do Araripe Palentological research center (CPCA) authorizes German Geoscientist Dr. Eberhard Frey to transport two cases containing limestone samples with fossils, without any commercial value, with the primary objective to proceed with paleontological studies at the Staatlisches Museum für Naturkunde in Karlsruhe, Germany, in accordance with the law decree number 4.146 on March 4, 1942.
—Rough translation of the legal documents

They state the limestone fossils are "of no commercial value", which is a statement challenged by numerous evidence, and even the existence of an illegal fossil trade based on currency. Frey also states the team was to have a Brazilian member, who was kicked due to false documentation. This contradicts Martill openly admitting that he had not, and will not be working with a Brazilian, as Brazil's fossil laws cite as a necessity. Frey has not elaborated further on this unnamed team member. He continues to message people over Email, in one case, addressing a user with this response:

Does the across-the board demand of getting fossils back to their countries of provenance only refer to published material that became recognized or all of them? If you refer to all of them you will launch a worldwide movement of thousands possibly millions of fossils. What about fossils that come to life after years because of a bad preservation as in this case? [...] The national museum of brazil burnt down because of technical problems, which, despite having been known, were not repaired by the state. This is sure not the fault of my Brazilian colleagues but mirrors the responsibility of some states for their protected heritage. It still grieves me thinking what that fire destroyed. [...] See, I really accept to return specimens that were stolen from a country. However, how do you want to teach people about the wealth of prehistoric life in the world, if you cannot show legal fossils and bringing them to life by working on them? The specimen we described is deposited in a secure collection room with fire alarms and doors. It is save and available for the scientific community and after the shut-down also for the public for a limited time in a high security glass case.
—Part of Frey's response via Email

He states clearly the fossil is in a better state exported, focusing the blame on a Brazilian museum that burnt down on September 2, 2018, and was not repaired despite the government knowing about the state of the building. Further looking-into shows the person who signed the documents is notorious for forging documents, and has various lawsuits against them. The text on the documents contradict previous statements, such a similar situation concerning fossils from the same locality of the Ubirajara holotype. The holotype was likely removed during the 1990s, with no legal authorization.


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