Phorodon lanzhouense Zhang et al. (1999)

was described from five apterae on an unknown host. The process on the frontal tubercles is described as “rounded” but appears mostly lacking in the illustration. Zhang et al. (1999) state that P. lanzhouense most resembles P. humulifoliae but differs in the structure of the mesosternal furca (two parts connected in the middle like a thread, rather than a solid structure), has shorter caudal setae, and has slightly longer siphunculi relative to the length of the cauda. More work is needed to confirm the validity of this species and determine if it belongs in Phorodon .