Fossil History

History of naming and fossil discovery

Initially in 1976, the first specimen of the pacific toothed oyster was misidentified and thought to be part of the Inoceramidae family. In 1988, Crampton reassessed this species of bivalve and clarified that it represents a species of Isognomon. Following this assessment, Crampton gave it a new name which is also currently used to identify this species. The scientific name that was given is Isognomon isognomon. I. isognomon was also clarified to be of separate as compared to other bivalves that occurs during the Late Cretaceous and Palaeocene period. The distinctive characters that distinguish Isognomon sp. against bivalves that occurred during Late Cretaceous and Palaeocene period are delicate resilifers and larger size shells.

(Stillwell, 2010; Crampton, 1988)