Apart from remaining the biggest marine turtle species ever discovered in Europe, and one of the major globally, the discovery of Leviathanochelys aenigmatica indicates that gigantism in maritime turtles was acquired independently, by unique lineages in excess of time.
An artist’s perception of Archelon ischyros. Graphic credit score: Nobu Tamura, spinops.blogspot.com.
Leviathanochelys aenigmatica lived through the Campanian age of the Late Cretaceous epoch, some 78 million yrs ago.
“Marine turtles had been widespread in the subtropical Higher Cretaceous epi-continental seas that the moment washed the coasts of the historical European archipelago,” mentioned Universitat Autònoma de Barcelona paleontologist Albert Sellés and his colleagues.
“But in contrast to its contemporaneous faunas from North The usa, in Europe no species surpassed the 1.5 m shell-size.”
With an estimated system length of up to 3.7 m, Leviathanochelys aenigmatica signifies the premier maritime turtle to have been located in Europe to day.
The largest regarded marine turtles these as the extinct genus Archelon, which grew to dimensions of 4.6 m very long and weighed up to 3.2 tons, lived in the seas bordering the North American continent toward the conclude of the Cretaceous interval.
The fossilized remains of Leviathanochelys aenigmatica were being identified at the locality of Cal Torrades in Spain.
They consisted of a fragmented but almost complete pelvis and components of the upper shell (carapace).
“The specimen possesses a distinctive prominence of bone that protrudes forwards from the front of the pelvis,” the paleontologists said.
“This characteristic differs to other maritime turtles, and signifies that Leviathanochelys aenigmatica represents a new taxon (group) of ancient maritime turtles.”
“This protrusion may possibly have connected to the respiratory process.”
Shell and pelvic girdle elements of Leviathanochelys aenigmatica: (a) dorsal watch of the specimen with the things disposed as they had been found, remarking in white the preserved carapace portion (b) visceral check out of the carapace with a superimposed interpretation of the shell components (c) dorsal check out of the preserved pelvic girdle without the need of the carapace, and (d) ventral perspective of the same component with the carapace asterisk marks suggest the spot of the autapomorphic accessory pubic method information of the accent pubic procedure in (e) dorsal and (f) ventral look at (g) near up check out of the posteromedial portion of the pubes, in ventral (higher image) and posterior view (decreased image), preserving section of the thyroid fossae separated by a thick bone construction (black arrow) (h) ventral see of the remaining acetabulum, illustrating the restrictions involving the pelvic bones (i) detail of the outer ornamented area of the ilium (j) histological segment of the costal 8, displaying a cancellous bone zone amongst the hugely vascularized internal and external cortices. Impression credit: Castillo-Visa et al., doi: 10.1038/s41598-022-22619-w.
The scientists estimate that the highest width of Leviathanochelys aenigmatica’s pelvis was 88.9 cm, which is slightly much larger than the biggest estimates for Archelon’s most effective acknowledged specimen (81 cm broad).
The duration of the pelvis from front to back again was approximated to be 39.5 cm, somewhat scaled-down than that of Archelon (46 cm extensive).
“The discovery of the new gigantic and strange chelonioid Leviathanochelys aenigmatica from the Center Campanian marine deposits of the Southern Pyrenees, which rivals in measurement to Archelon, sheds a gentle on the diversity of marine turtles and on how the phenomenon of gigantism in these teams was also transpiring in Europe,” the authors said.
“Despite the scarcity and fragmentary mother nature of the specific, the new proof not only raises the taxonomic variety of the Late Cretaceous maritime turtle biota in Europe, but also opens a new line of exploration and raises new concerns, in buy to resolve the evolutionary mechanisms and ecological pressures that could have favored the independent evolution of colossal (over 2.5 m in shell size) marine turtles in many lineages, particularly in the course of the Late Cretaceous epoch.”
The findings are published in the journal Scientific Experiences.
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O. Castillo-Visa et al. 2022. A gigantic weird marine turtle (Testudines: Chelonioidea) from the Middle Campanian (Late Cretaceous) of South-western Europe. Sci Rep 12, 18322 doi: 10.1038/s41598-022-22619-w
