Sheinwoodian

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The Sheinwoodian is a short slice of time in the Silurian period, within the Wenlock epoch. It lasted about 2.3 million years, roughly from 432.9 million years ago to 430.6 million years ago. It comes after the Telychian and before the Homerian.

Named after Sheinwood village, north of Much Wenlock in Shropshire, England, its main reference section is in the Buildwas Formation of Shropshire.

Lower and upper boundaries:
- Lower boundary: not precisely defined yet; placed near the boundary with the conodont Pterospathodus amorphognathoides. There are proposed GSSP sections at Hughley Brook and Apedale in the UK.
- Upper boundary: defined by the first appearance of the graptolite Cyrtograptus lundgreni, with the GSSP at Sheinton Brook, Homer, England.

In the geologic timescale, the Sheinwoodian is the age at the end of the Wenlock epoch, and the stage is part of the broader Silurian period.