Aissellidae
Aissellidae is a family of extinct marine bivalve mollusks belonging to the order Pectinida. Fossils of aissellids are found in rocks dating from the Triassic period. The family is characterized by its weakly to moderately convex, equivalve shells, meaning both valves are of similar size and shape. The left valve is typically slightly larger than the right. The external surface of the shell is usually ornamented with concentric growth lines and sometimes fine radial ribs. Aissellids possessed a ctenoid hinge, meaning the hinge line was lined with small comb-like teeth.
These bivalves were sessile organisms, likely attaching themselves to the seafloor or other substrates. Their morphology