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A new genus and species of fordilloid pelecypod, Pojetaia runnegari gen. et sp. nov., is described from the lower part of the Parara Limestone, Yorke Peninsula, South Australia. Establishing the age of the sample on an international scale is difficult, as with almost all Early Cambrian formations, but evidence tends to suggest that this is the oldest pelecypod so far recorded. Clearly defined hinge teeth and sockets on both valves and on internal moulds help to confirm the pelecypod placement of fordilloids.
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Peter A. Jell (1980) studied this question.
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