Some 25 years after the initial finds, an international team of paleontologists now describes “Issi saaneq” in the latest issue of the scientific journal Diversity. The first author of the work is Victor Beccari, from the NOVA School of Science and Technology in Lisbon, Portugal, and the Bayerische Staatssammlung für Paläontologie und Geologie in Munich, Germany, in collaboration with researchers from the Lourinhã Museum in Portugal, Martin Luther University Halle-Wittenberg in Germany, and Geomuseum Faxe and the University of Copenhagen, both in Denmark.
The new dinosaur name
honors the local Inuit language; meaning “cold bone”. The plant-eating dinosaur
lived during the late Triassic approximately 214 million years ago. During that
time, the supercontinent Pangaea broke up and the Atlantic Ocean began to form.
Issi saaneq is among the first sauropodomorphs (the dinosaur group from which
later evolved the largest terrestrial animals of all times) to have lived on
the northern hemisphere. It was a medium-sized, long-necked dinosaur, and the
first sauropodomorph to have reached latitudes over 40° North.
“It is exciting to
discover close relatives of the long-known Plateosaurus, of which more than one
hundred individuals were found here in Germany until now” says Oliver Wings, a
coauthor from the Martin Luther University in Halle-Wittenberg, Germany.
“Especially with such excellent preservation and two rather complete skulls” he
adds.
The first expeditions
to recover vertebrate fossils in East Greenland date back to the 19th century,
and numerous tetrapods have been described from there until now. These fossils
span from the Devonian period to the Jurassic, and contain some iconic animals
such as Ichtyostega, one of the first vertebrates to leave the oceans. During
the Late Triassic, East Greenland was connected to what is now Europe. It was a
transitional environment between the dry interior of Pangea, and the humid
peripheral parts of the continent. At this point in time, the fauna of East
Greenland was diverse, with large fishes, amphibians, phytosaurs, pterosaurs,
and some of the first dinosaurs. While dinosaurs are known for almost complete
skeletons and numerous trackways in Jameson Land, East Greenland, only a few of
their bones are already prepared and they never have been thoroughly described.
This changes with the
description of two almost complete skulls of this plant-eating dinosaur. The
work was published in the open access journal Diversity this Wednesday,
November 3, 2021, by an international team of researchers from Brazil,
Portugal, Germany, and Denmark.
The remains of these
dinosaurs were recovered by palaeontologists from Harvard University in
expeditions to Greenland during the early 1990s. One of these specimens was
initially assigned to Plateosaurus, an iconic Triassic sauropodomorph found in
Germany, France, and Switzerland. In the present, the dinosaur fossils were
studied in detail by Victor Beccari for his master’s thesis at the Master in
Palaeontology, at the NOVA School of Science and Technology, under the
supervision of Octávio Mateus from the same university. During his studies,
enough anatomical differences in the skull bones allowed Beccari to separate
the Greenland dinosaur Issi from the European Plateosaurus.
“The two skulls are
unique in many aspects of their anatomy, such as their bone proportions and
shapes” says Beccari. “These specimens certainly pertain to a new species, Issi
saaneq”. “Back then, the Earth was going through climate changes that allowed
for the first plant-eating dinosaurs to reach Europe and beyond” explains the
coordinator of the work, Lars Clemmensen, from the University of Copenhagen.
Clemmensen studies of the geology of East Greenland have dated the
dinosaur-wilding outcrops of Jameson Land in his previous works with Dennis
Kent (USA)
To study the material,
both skulls were scanned using micro-CT-scan and segmented, which allowed for
the visualization of internal structures and bones that were still covered by
sediment, and the creation of 3D models that are available for download on the
website MorphoSource. This digitization provide the basis for a thorough
description of the specimen, but also made it possible for Beccari to work on
his thesis during the lockdowns of Covid-19.
“This is the third new
vertebrate fossil species that our team named for Greenland, which shows the
scientific importance of that territory” says Octávio Mateus adding “It’s
spectacular to have a thesis in our Master in Paleontology at Nova University
of Lisbon with these results and quality”.
The two skulls from
Issi saaneq pertain to a juvenile and a possible subadult. The differences,
other than size, are minor and relate solely to proportions. The Greenland
dinosaur differs from all other sauropodomorphs described so far by a set of
unique features, but also show similarities with Brazilian dinosaurs, such as
Macrocollum and Unaysaurus. The Brazilian dinosaurs are almost 15 million years
older than Issi saaneq. Together with the European Plateosaurus, these
dinosaurs and Issi saaneq form the group of plateosaurid sauropodomorphs.
Plateosaurids were bipedal and gracile animals, reaching 3 to 10 meters in
length.
The new dinosaur
increases the diversity of dinosaurs during the Late Triassic (235-201 million
years ago) and allows us to start retracing the evolutionary routes and timing
for the iconic group of sauropods that roamed the Earth for almost 150 million
years. The skulls of Issi saaneq are currently part of an exhibition in the
Museu da Lourinhã, Portugal. More specimens from East Greenland, including a
complete skeleton, were already collected and are presently on display at the
Geocenter Møns Klint in Denmark awaiting further studies. Some material is
currently also under preparation in the Dinosaur Park Münchehagen in Germany.
After the final studies, all specimens will be curated by the Natural History
Museum of Denmark.
Source: https://www.fct.unl.pt/en/news/2021/11/new-species-214-million-years-old-dinosaur-found-greenland
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