Protochiton

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Protochiton
Temporal range: Eocene [1]
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Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Mollusca
Class: Polyplacophora
Family: Protochitonidae
Genus: Protochiton
Ashby, 1925

Protochiton is an extinct genus of polyplacophoran molluscs. Protochiton became extinct during the Eocene period. [1]

Chiton class of molluscs

Chitons are marine molluscs of varying size in the class Polyplacophora, formerly known as Amphineura. About 940 extant and 430 fossil species are recognized.

The Eocene Epoch, lasting from 56 to 33.9 million years ago, is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the Grande Coupure or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain.

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References

  1. 1 2 van Belle, R. A. (1981). Catalogue of Fossil Chitons. ISBN   90 6279 018 6.