The earliest cormose rhizomorph of putative lycopsid affinity from the Middle Devonian of West Junggar, Xinjiang, China

Impression fossils of a cormose rhizomorph are described from the Givetian (late Middle Devonian) Hujiersite Formation, Hoxtolgay, West Junggar, Xinjiang, Northwest China. The rhizomorph is bulbous, with densely arranged, oval rootlet bases enclosing orbicular vascular bundle scars, exhibiting considerable resemblance to that of the Late Devonian-Carboniferous rhizomorphic lycopsid of Isoetales sensu stricto. The present specimens may represent the earliest cormose lycopsid rhizomorph. Their implications for the origin and early evolution of rhizomorphic lycopsids are discussed.