Anomia (bivalve)
Anomia is a genus of saltwater clams, marine bivalve mollusks in the family Anomiidae. They are commonly known as jingle shells because when a handful of them are shaken they make a jingling sound, though some are also known as saddle oysters. This genus first appeared in the Permian period of China, Italy, and Pakistan. "Anomia" species are common in both tropical and temperate oceans and live primarily attached to rock or other shells via a calcified byssus that extends through the lower valve. "Anomia" shells tend to take on the surface shape of what they are attached  to; thus if an "Anomia" is attached to a scallop shell, the shell of the "Anomia" will also show ribbing. The species "A. colombiana" has been found in the La Frontera Formation of Boyacá, Cundinamarca and Huila of Colombia. Species. Species: Reassigned species. As "Anomia" was erected very early in paleontology, several species have been reassigned; most of them are now recognized as brachiopods.