''Matthevia'' is a genus of

Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...

molluscs, perhaps related to the

chiton Chitons () are marine molluscs of varying size in the class Polyplacophora ( ), formerly known as Amphineura. About 940 extant and 430 fossil species are recognized. They are also sometimes known as sea cradles or coat-of-mail shells or suck ...

s. It consists of repeated monoplacophoran-like shells; according to one hypothesis, chitons arose when these tall shells began to overlap over the generations. The tall element of the shell was retained and forms the tips of modern chiton plates. There are distinct head, 'centre', and tail valves, which occur approximately in the ratio 1:5:1 — suggesting a seven-plated configuration. Matthevia was first described by Charles D. Walcott in 1885.Walcott, C. D., 1885, Note on some Paleozoic pteropods: Am. Jour. Sci., v. 30, p. 17-21.

References

Prehistoric chiton genera Cambrian molluscs Cambrian molluscs of North America Cambrian first appearances Early Ordovician extinctions Cambrian genus extinctions {{paleo-mollusc-stub

See also

References