Phymosteus liui is an extinct large selenosteid arthrodire placoderm known from the Lower Famennian Xiejingshi Formation of Shimen County, Hunan province, in central China.

[1] The holotype and only known specimen of P. liui is a V-shaped median dorsal plate with a distinctive texture.

[1] Because the fossil is incomplete, its exact relationship to the other selenosteids can not be satisfactorily determined.

This article about a placoderm is a stub.

You can help Wikipedia by expanding it.