Edestidae
Encyclopedia
Edestidae is an extinct and poorly known family of shark
s. They possessed a unique "tooth-whorl" on the symphysis
of the lower jaw as well as pectoral fins supported by long radials. The palatoquadrate
was either fused to the skull or reduced. It is possible that they may belong to Holocephali
.
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s. They possessed a unique "tooth-whorl" on the symphysis
Symphysis
A symphysis is a fibrocartilaginous fusion between two bones. It is a type of cartilaginous joint, specifically a secondary cartilaginous joint.1.A symphysis is an amphiarthrosis, a slightly movable joint.2.A growing together of parts or structures...
of the lower jaw as well as pectoral fins supported by long radials. The palatoquadrate
Palatoquadrate
In some fishes, the palatoquadrate is the dorsal component of the mandibular arch, the ventral one being Meckel's cartilage....
was either fused to the skull or reduced. It is possible that they may belong to Holocephali
Holocephali
The subclass Holocephali is a taxon of cartilaginous fish, of which the order Chimaeriformes is the only surviving group.Holocephali has an extensive fossil record that starts during the Devonian period. However, most fossils are teeth, and the body forms of numerous species are not known, or, at...
.