A new species of early crocodyloid crocodilian being named Asiatosuchus oenotriensis has been discovered by a team of paleontologists from the Universidad Nacional de Educación a Distancia and the Universidad de Salamanca in Spain.
Skull of Asiatosuchus oenotriensis, holotype, from the Middle Eocene site of Casaseca de Campeán, Spain. Image credit: Narváez et al., doi: 10.1002/ar.25422.
The newly-identified crocodyloid species roamed our planet during the Middle Eocene epoch, between 48 and 41 million years ago.
The prehistoric animal belongs to Asiatosuchus, an extinct genus of crocodyloid crocodilians that lived in Europe and Asia during the Paleogene period (66-23 million years ago).
“During the Paleogene, various crocodyloids with generalized rostra (i.e., not elongated) occurred in Europe, with the Middle Eocene being particularly notable in terms of relative abundance and diversity, but also including remains from the Late Paleocene and perhaps the Early Oligocene and Late Neogene,” said lead author Dr. Iván Narváez and his colleagues.
“Many of the Eocene crocodyloid remains have been associated with an ‘Asiatosuchus-like complex’.”
“The genus Asiatosuchus was established by paleontologist Charles Mook in 1940, who defined the species Asiatosuchus grangeri based on an incomplete lower jaw and some skull fragments from the Middle Eocene of the Irdin Manha Formation, in Mongolia.”
“After the definition of Asiatosuchus grangeri, several other eusuchian forms represented by generally isolated or scarce remains from the Paleocene to Oligocene of Europe, Asia and North America have been described, being recently recognized as composing an Asiatosuchus-like complex.”
The fossilized remains of two Asiatosuchus oenotriensis individuals of similar size were discovered in the 1980s at the site of La Laguna in Spain.
The specimens include a nearly complete skull and an almost complete left lower jaw.
“La Laguna fossil-site is located about 1 km to the north of the village of Casaseca de Campeán, about 20 km to the south of Zamora city in the Tierra del Vino region, Zamora province, Spain,” the paleontologists said.
“This region forms part of the Western sector (Ciudad Rodrigo Sub-Basin) of the Duero Basin.”
“The Duero Basin is the largest continental Cenozoic basin present in the Iberian Peninsula.”
According to the authors, the discovery of Asiatosuchus oenotriensis increases knowledge on the diversity and distribution of the ‘Asiatosuchus-like complex’ crocodyloids.
“Asiatosuchus oenotriensis adds valuable information to the knowledge of the systematics of the relatively diverse crocodyliform fauna from the Spanish Duero Basin,” they said.
The team’s paper was published in The Anatomical Record.
_____
Iván Narváez et al. A new Crocodyloidea from the Middle Eocene of Zamora (Duero Basin, Spain). The Anatomical Record, published online March 5, 2024; doi: 10.1002/ar.25422