[2] Like other members of the subfamily Hypoptopomatinae, Pseudotocinclus is primarily herbivorous and is more commonly found at or near the upper portion of the water column.

It lives in close association with sub-surface structures provided by submerged tree branches, aquatic macrophytes, and terrestrial grass blades growing along creek margins and extending into the water.

[2] The genus Pseudotocinclus can be distinguished from other genera of the subfamily Hypoptopomatinae by the presence of a caudal peduncle that is nearly square in cross section from the posterior base of the dorsal fin to the caudal fin, as well as having 26 or more plates along the lateral line, a dorsally positioned eye, an exposed preopercle, and an abdomen covered with numerous small platelets.

In addition, P. tietensis has four transverse dark-brown bands on the dorsum coalesced with the midlateral stripe instead of three as in the other two species.

P. juquiae is distinguished from the other species by having a very prominent and conspicuous ring structure around the eye.