Phymosteus

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]

Phymosteus Temporal range: Early Famennian[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	†Placodermi
Order:	†Arthrodira
Suborder:	†Brachythoraci
Family:	†Selenosteidae
Genus:	†Phymosteus Wang and Zhu, 2004
Species:	†P. liui
Binomial name
†Phymosteus liui Wang and Zhu, 2004

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.