Inoceramidae

Inoceramidae is an extinct family of marine bivalve mollusks that lived from the Early Jurassic to the Late Cretaceous periods. They are commonly known as the "inoceramids". These large, thick-shelled clams were widespread in the ancient oceans and are important index fossils for dating Late Cretaceous sedimentary rocks. Their shells are often found as fragments due to their size and brittle nature.

The family is characterized by its distinctive shell ornamentation, typically consisting of concentric growth rings. The shell material was often prismatic, leading to their common name, which derives from the Latin words "in " (in) and "ceram" (wax), referring to their resemblance to wax-covered vessels. Inoceramids lived in a variety of marine environments, from shallow to deep waters, and some species were epibenthic, attaching to the seafloor.

Fossil inoceramids are particularly abundant in chalk deposits, and their presence can indicate the depositional environment and age of the rock. Their extinction at the end of the Cretaceous is linked to the K-Pg extinction event. Studying inoceramids provides insights into ancient marine ecosystems, paleoceanography, and the evolutionary history of bivalves. Their large size and abundance made them a significant component of Mesozoic marine food webs.