Pseudobunocephalus lundbergi can be distinguished from all congeners by having the following unique characters within the genus: dorsal surface of skull ornamented with numerous bony knobs of equal size; distinct anterior and posterior cranial fontanels separated by a bony epiphyseal bar formed between the frontals; infraorbital canal exits from the sphenotic and extendsanteriorly past eye, bearing up to four pores; premaxilla without a posterolateral limb; and fifth centra with posteriorly directed processes that articulate with skeletal elements of the dorsal fin (Ref. 78999).