Paleontologists have found a new species of spiny shark that inhabited the Devonian sea of northeastern Spain 408 million years ago.
Hector Botella from the University of Valencia in Spain; Carlos-Martinez-Perez from the University of Bristol in the UK, and Rodrigo Soler-Gijon from the Universidad Complutense in Spain report on the new species, named Machaeracanthus goujeti, in the journal Geodiversitas.
The research team found spines, shoulder bones, and scales from M. goujeti in sedimentary beds in the Nogueras Formation of Teruel, Spain. The area was what is known as an epicontintental sea—a large, shallow body of salt water that is conducive to breeding–and therefore an attractive place to live for Machaeracanthus goujeti.
M, goujeti was a meter-long sea-faring creature that resembled modern-day sharks and bony fish. It belonged to a class of fish known as Acanthodii—a group that is now all extinct. Acanthodii had bodies shaped like sharks, with paired fins and an upturned tail. Spines and scales are all that remain of Acanthodii for paleontologists to study—thus the name “spiny sharks.”
The study analyzed other specimens from the genus Machaeracanthus, some found more than 150 years ago. They discovered that the new species has spine morphology consistent with others in the same genus. The new find is particularly close in shape and size to M. peracutus, a species discovered in 1857.
The researchers examined M. goujiti fossils that belonged to a young individual in order to determine development patterns for the new species. They found that the way the spine grew was markedly different from the usual development of spiny shark spines, indicating that M. goujeti was closer in relation to modern sharks, and quite possibly a link between the ancient spiny sharks and today’s sharks.
The fossils are housed in the Paleontology Museum of Zaragoza, Spain.
Find the study in the December 2012 issue of Geodiversitas.