Paleontologists have discovered a new genus and species of pancinisaur lizard, named Acutodon villeveyracensis, from an upper jaw fossil found in southern France. This discovery extends the presence of this lineage in Europe back by at least 30 million years.
Paleo-artistic restoration of Acutodon villeveyracensis, the oldest known member of the pansinisaurid family found in Europe. Image credit: Olivier Jansen.
Pansinisaurus Anguimorphs represent an evolutionary group of lizards that originated in the Early Cretaceous period.
Currently, this lineage exists in only one surviving species: the endangered Chinese Crocodile Lizard (Sinisaurus crocodilius), found in small forest streams of southeastern China and northern Vietnam.
Scientists estimate that only a few hundred individuals of this species remain, facing threats from habitat destruction, poaching, and climate change.
“The Chinese Crocodile Lizard represents the only extant member of the pan-sinisaurus clade (comparable to sinisaurids),” stated Dr. Olivier Jansen, paleontologist at the Institute of Paleontology, Evolutionary Paleoecological Systems, and Paleoprimates of the University of Poitiers and CNRS, alongside his colleagues.
“This species is concentrated in small subpopulations within the lowland forests of southeastern China and northern Vietnam.”
“They face severe risks from habitat loss and rampant poaching, exacerbated by demand for food, pharmaceuticals, and the illegal pet trade.”
“Chinese Alligator Lizards are also impacted by climate change. Adapted to clean streams in dense vegetation of remote evergreen forests, they depend on consistently moderate temperatures each year.”
“Despite being on the edge of extinction, the evolutionary history of this group remains inadequately understood, and the species may vanish before we unravel the mystery of its origins.”
The newly identified species, Acutodon villeveyracensis, thrived during the Campanian period of the Late Cretaceous, approximately 83 million years ago in what is now France.
“This Cretaceous record marks the oldest occurrence of a pan-sinisaurian lizard in Europe,” the paleontologists emphasized.
“It predates the presence of this clade in Europe by about 30 million years, raising intriguing questions about the paleontological history of pancinisaur lizards.” The holotype specimen of Acutodon villeveyracensis was excavated near Villeverac in the Hérault region of France.
The fossilized specimen consists of an upper jaw bone measuring approximately 2.8 cm (1.1 inches) long, featuring a row of narrow, arched teeth.
This lizard exhibited several unique anatomical traits shared with both modern and extinct alligator lizards, notably the unique tooth replacement structures known as resorption pits.
The researchers concluded that the distinct combination of features warranted the classification of a new genus and species.
“Acutodon villeveyracensis is categorized as a pansinisaur angimorph based on its toothed upper jaw, which shares numerous features with both extant fossils of the Chinese Alligator Lizard and its relatives,” the researchers explained. These features include tall, tapered, and recurved teeth with constricted bases and resorption pits.
By analyzing the skull proportions of existing alligator lizards, scientists estimate that Acutodon villeveyracensis could have exceeded 1 meter (3.3 ft) in length.
“This species was indeed a predator, competing in size and habitat with other large squamates in its ecosystem, such as the terrestrial monsterosaurids and the aquatic mosasaurs,” the researchers added.
The unique alignment of teeth in Acutodon villeveyracensis—characterized by thin, tapered, and recurved teeth—supports a diet that likely included fish. Analogously to the Chinese Crocodile Lizard, it may have also preyed on other small vertebrates like frogs, salamanders, and Albanerpetonidae in the freshwater wetlands of Villevérac (Hérault, France).
The discovery of Acutodon villeveyracensis is detailed in a recent paper published in the Journal of Vertebrate Paleontology.
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Olivier Jansen and colleagues. A new pancinisaur lizard (Anguimorpha) discovered in the lower Campanian region of Villeverac (Hérault, France). Journal of Vertebrate Paleontology, published online on May 20, 2026. doi: 10.1080/02724634.2026.2636649
Source: www.sci.news
