Abstract: According to newly collected and well preserved specimens, herbaceous lycopsids Colpodexylon gracilentum Dou and Colpodexylon laminatum Dou from the late Middle Devonian of Xinjiang, NW China are reduced to C. gracilentum, for which a neotype is designated and emended diagnosis is given. Colpodexylon gracilentum has leaves with three nearly equal segments, an elliptical sporangium adaxially attached by a pad on the isomorphic sporophyll.

Key words: Colpodexylon, Devonian, lycopsid, neotype, Xinjiang