Sarcoprion
Sarcoprion is an extinct genus of eugeneodont holocephalan from the Permian of Greenland. Similar to other helicoprionids such as Agassizodus and Helicoprion, it possessed tooth whorls on the symphysis of the jaw as well as flattened, pavement-type teeth. It is distinguished from other members of its family by the presence of sharp, symphyseal teeth on both the upper and lower jaws. The tooth whorl on the lower jaw bore sharp, compact tooth crowns, while a row of backward facing, triangular teeth was present on the roof of the mouth. The preserved material does not show evidence of a distinct upper jaw, implying it may have been fused to the cranium, reduced, or lost entirely. The type and only species in the genus is ''S. edax.''
Research history and naming
The first four Sarcoprion fossils were first discovered during the 1930s by paleontologist Eigil Nielsen, and originated inside concretions from the Foldvik Creek Formation of East Greenland. These specimens were described by Nielsen in 1952, and the most complete of them was designated as the holotype. Part of the holotype specimen was collected in 1932, and other fragments were collected later in 1937. Nielsen suspected that a larger portion of this specimen was originally preserved, but that it had most likely become broken apart and lost due to erosion. A block of matrix containing the remainder of this specimen's skull has since been identified.Researcher Leif Tapanila began research on S. edax fossils at the Natural History Museum of Denmark in 2023. As of 2026 the skull of the animal is being studied via CT scanning.
Etymology
The genus name is derived from the Greek roots sarcos, meaning "flesh", and prion, meaning "saw". The species name, edax, means "gluttonous".Description
Sarcoprion had a thin, pointed snout, with two opposing rows of large teeth along the midline of its upper and lower jaws. The rostrum was greatly elongated compared to its relatives with comparable known skull material. The most complete known Sarcoprion specimen consists of a skull and lower jaws which are nearly long, and the total length of the animal was estimated to be up to by paleontologist John A. Long.Nielsen suggested that, based on his reconstruction of the genus' skull and lower jaw, Sarcoprion was likely incapable of closing its mouth. Rows of flattened teeth were present along the lateral surfaces of the mouth in addition to the midline tooth whorls, and Nielsen thought these were likely armor for the snout rather than useful for feeding.