A new small-sized titanosaur discovered in southern France

Garrigatitan meridionalis is a new dinosaur species belonging to titanosaurs, from the Upper Cretaceous (around 75 million years ago) of Velaux-La Bastide Neuve site in Provence (France). It comes from the same site and time frame as Atsinganosaurus velauciensis, another titanosaur closely related to Garrigatitan that was redescribed in 2018 by the same team who just have published their new discoveries in Historical Biology.

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ike Atsinganosaurus, the bones of Garrigatitan indicate subadult and possibly adult individuals ranging from only 4 to 6 meters long for the largest known adult length of 12 meters, which is relatively small by sauropod standards that usually exceed 15 meters in length. This is the finding that Benjamin Jentgen-Ceschino, FNRS PhD student at the EDDYLab  (Geology Research Unit / Faculty of Science) of the University of Liège and at the AMGC in the Vrije Universiteit Brussel, has been able to establish thanks to bone histology, i.e., the microscopic study of bone tissue.

Given the insular context of this new taxon that was prevailing by that time in the south of France, this process of reduction in size is probably related to the so-called ‘Island Rule’, i.e., that small-sized species tend to become giants on islands, and big species tend to dwarf, for ecological reasons drastically different from those of the mainland (e.g., reduced predation, different resource availabilities, etc.).

Such study indicates that several titanosaurian lineages colonized and could sustain on islands of southern France for a long time during the Late Cretaceous, by decreasing drastically their body size.

Scientific reference

Verónica Díez Díaz, Géraldine Garcia, Xabier Pereda Suberbiola, Benjamin Jentgen-Ceschino, Koen Stein, Pascal Godefroit & Xavier Valentin (2020), A new titanosaur (Dinosauria: Sauropoda) from the Upper Cretaceous of Velaux-La-Bastide Neuve (southern France), Historical Biology,.

Contact

Benjamin JENTGEN, PhD Researcher, FRIA grantee - Fund for Scientific Research - FNRS