Palaeonema

Palaeonema an extinct genus of nematodes from the Early Devonian. It contains only one species, Palaeonema phyticum, and is the only member of the family Palaeonematidae. "P. phyticum" is the oldest known fossil nematode, and was parasitic upon the Rhynie chert plant "Agalophyton".
According to George Poinar Jr. (2011), the family Palaeonematidae is placed in the order Enoplida.